H400015 Hydraulic Driven Air Compressor

Product Information: Hydraulic Driven Air Compressor

Specifications

• Model Numbers: H400006 | H400015
• Registered Trademarks: Variable Displacement Pumps

General Information

VMAC is a leading provider of vehicle-mounted air compressors.
Please note that VMAC cannot provide hydraulic circuit designs or
consult on specific hydraulic installations. It is recommended to
work with a local hydraulic expert to design and install the
hydraulic circuit that will power the Hydraulic Driven Air
Compressor system.

Introduction

To order parts for your Hydraulic Driven Air Compressor, please
contact a VMAC dealer. They will require the VMAC System ID (see
page 33), part number, description, and quantity. You can find the
nearest dealer online at vmacair.com/dealer-locator
or call 1-877-912-6605.

Additional Support

For additional resources such as installation manuals,
illustrated parts lists, the VMAC Knowledge Base, and air tool
consumption guides, please visit vmacair.com/support/.

Safety

Important Safety Notice: Only follow proven service procedures.
Any deviation from the instructions in this manual must be done
with caution and consideration for safety. VMAC will not be held
responsible for any damages, injuries, or loss resulting from
improper adherence to the procedures in this manual or standard
safety practices. Prior to any service operations, ensure that
safety is prioritized and contact VMAC Technical Support if there
are any questions or for further information.

This manual contains various warnings, cautions, and notices
that must be followed to reduce the risk of personal injury during
installation, service, or repair. Improper installation, service,
or repair may damage the equipment or make it unsafe.

FAQ

Q: Can VMAC provide hydraulic circuit designs or consultation

for specific hydraulic installations?

A: No, VMAC recommends working with a local hydraulic expert to
design and install the hydraulic circuit for the Hydraulic Driven
Air Compressor system.

Q: How can I order parts for my Hydraulic Driven Air

Compressor?

A: To order parts, please contact a VMAC dealer and provide them
with the VMAC System ID, part number, description, and quantity.
You can find the nearest dealer online at
vmacair.com/dealer-locator or call 1-877-912-6605.

Q: Where can I find additional support and resources?

A: You can find installation manuals, illustrated parts lists,
the VMAC Knowledge Base, and air tool consumption guides at
vmacair.com/support/.

®
Hydraulic Driven Air Compressor Installation and Owner’s Manual (Includes Service Instructions)
H400006 | H400015
www.vmacair.com

Table of Contents
General Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Hydraulic Driven Air Compressor Installation Manual . . . . . . . . . . . 11
Installation Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Mounting Locations and Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Speed Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Hydraulic Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Hydraulic Fluid and Line Sizing Recommendations . . . . . . . . . . . . . . . . . . 19 Hydraulic Driven Air Compressor Harness Reference . . . . . . . . . . . . . . . 22 Electrical Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Installing the Hydraulic Driven Air Compressor System. . . . . . . . . . . . . 26 Testing the Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Performance Testing and System Adjustments. . . . . . . . . . . . . . . . . . . . . 29
Hydraulic Driven Air Compressor Owner’s Manual . . . . . . . . . . . . . . 31
Identifying Your System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 System Components and Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 System Operation (What to Expect at Start Up). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Cold or Hot Weather Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Display Box Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 System Adjustments (Diagnostics Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Limp Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 General Maintenance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Maintenance and Repair Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Regular Inspection Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 500 Hour / 1 Year Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Diagnostics and Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Hydraulic Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Air Receiver Tank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Recommended Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 Accessory Products from VMAC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Error and Service Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 Warranty Registration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

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Document: 1930387 Changes and Revisions

Revision

Revision Details

D

ECN: 22-061 Warming parameter update

E

ECN: 22-101 Hyd. requirements.

F

ECN: 23-198 Add H400015.

Revised by
MSP MSP MSP

Checked by Eng.
Tech. Qual. Mech. Elec. BJG CAB MSP AWM GJM N/A MSP N/A GJM N/A MSP N/A

Implemented
13 June 2022 6 Jul. 2022 19 Sept. 2023

Additional Application Information
This manual applies to: H400006 | H400015.
· Not compatible with “load sensing” variable displacement pumps. · Requires VMAC Closed Center Manifold if used with “pressure compensated”
variable displacement pumps:
Registered Trademarks
All trademarks mentioned in this manual are the property of their respective owners. VMAC’s use of manufacturers’ trademarks in this manual is for identification of the products only and does not imply any affiliation to, or endorsement of said companies.
Loctite®, Loctite® 242 and Loctite® 567 are registered trademarks of Henkel AG & Company KGaA. Eaton Aeroquip® is a registered trademark of EATON AEROQUIP INC. Viton® is a registered trademark of The Chemours Company.

Important Information
The information in this manual is intended for certified VMAC installers who have been trained in installation and service procedures and/or for anyone with mechanical trade certification who has the tools and equipment to properly and safely perform the installation or service. Do not attempt installation or service without the appropriate mechanical training, knowledge and experience. Follow all safety precautions. Any fabrication for correct fit in modified vehicles must follow industry standard “best practices”.

Notice
Copyright © 2021 VMAC Global Technology Inc. All Rights Reserved. These materials are provided by VMAC for informational purposes only, without representation or warranty of any kind, and VMAC shall not be liable for errors or omissions with respect to the materials. The only warranties for VMAC products and services are those set forth in the express warranty statements accompanying such products and services, if any, and nothing herein shall be construed as constituting an additional warranty. Printing or copying of any page in this document in whole or in part is only permitted for personal use. All other use, copying or reproduction in both print and electronic form of any part of this document without the written consent of VMAC is prohibited. The information contained herein may be changed without prior notice.
Printed in Canada

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General Information
VMAC is unable to provide hydraulic circuit designs or consult on specific hydraulic installations. We recommend working with a local hydraulic expert to design and/or install the hydraulic circuit that will power the Hydraulic Driven Air Compressor system.
Introduction
This manual provides operating instructions, specifications, adjustment, maintenance and warranty information for the VMAC Hydraulic Driven Air Compressor systems. Read this manual prior to servicing or operating the compressor system. Follow all safety precautions when servicing or operating the VMAC system as moving fan blades and other rotating components pose an extreme hazard. Proper service and repair are important to the safety of the operator and the safe, reliable operation of the equipment. Always use genuine VMAC replacement parts. The procedures described in this manual are the only approved methods of service and operation.
Ordering Parts
To order parts, contact a VMAC dealer. The dealer will ask for the VMAC System ID (see page 33), part number, description and quantity. Locate the nearest dealer online at www.vmacair.com/dealer-locator or call 1-877-912-6605.
Additional Support
Additional resources such as installation manuals, illustrated parts lists, the VMAC Knowledge Base, air tool consumption guides, etc. are available at https://www.vmacair.com/support/.

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Safety
Important Safety Notice
The information contained in this manual is based on sound engineering principles, research, extensive field experience and technical information. Information is constantly changing with the addition of new models, assemblies, service techniques and running OEM changes. If a discrepancy is found in this manual, contact VMAC Technical Support prior to initiating or proceeding with installation, service or repair. Current information may clarify the issue. Anyone with knowledge of such discrepancies, who proceeds to perform service and repair, assumes all risks.
Only proven service procedures are recommended. Anyone who departs from the specific instructions provided in this manual must first ensure that their safety and that of others is not being compromised, and that there will be no adverse effects on the operational safety or performance of the equipment.
VMAC will not be held responsible for any liability, consequential damages, injuries, loss or damage to individuals or to equipment as a result of the failure of anyone to properly adhere to the procedures set out in this manual or standard safety practices.
Safety should be the first consideration when performing any service operations. If there are any questions concerning the procedures in this manual, or more information is required, please contact VMAC Technical Support prior to beginning work.
Safety Messages
This manual contains various warnings, cautions and notices that must be observed to reduce the risk of personal injury during installation, service or repair and the possibility that improper installation, service or repair may damage the equipment or render it unsafe.
This symbol is used to call attention to instructions concerning personal safety. Watch for this symbol; it points out important safety precautions, it means, “Attention, become alert! Your personal safety is involved”. Read the message that follows and be aware of the possibility of personal injury or death. As it is impossible to warn of every conceivable hazard, common sense and industry standard safety practices must be observed.
This symbol is used to call attention to instructions on a specific procedure that if not followed may damage or reduce the useful life of the compressor or other equipment.
This symbol is used to call attention to additional instructions or special emphasis on a specific procedure.

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Safety Precautions
As it is impossible to warn of every possible hazard that may result from operating this system, common sense and industry standard safety practices must be observed.
Read this information before operating the compressor for the first time. Follow the information and procedures in this manual for operation, maintenance and repair. Observe the following items to reduce the chance of personal injury or equipment damage.
Follow all safety precautions for mechanical work. Moving belts and rotating components are an extreme hazard. Stay clear of all moving parts when the system is operating. Only qualified personnel should perform maintenance and repair on system components and only while the system is properly shut down.
Proper service and repair are important to the safety of the service technician and the safe, reliable operation of the equipment. Always use genuine VMAC replacement parts.
The procedures described in this service manual are effective methods of service and repair. Some procedures may require the use of tools specially designed for a specific purpose. Anyone using a replacement part, service procedure or tool must first determine that neither their safety nor the safe operation of the equipment will be compromised by the replacement part, service procedure or tool selected.
Burn Hazard
· The compressor system gets very hot during operation, contact
with the components or the oil can cause serious injury. Allow sufficient time for the system to cool before performing service.
· Never allow any part of your body to contact the compressor
components.
Personal Safety
· Do not breathe the compressor air. Vaporized oil is a respiratory
hazard.
· Always use the appropriate personal protective equipment,
particularly eye and hearing protection when operating air powered equipment.

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Fire and Explosion Hazard
· Vaporized oil propelled by high pressure air is an explosive mixture. · Fire in the compressor can cause an explosion and flame projection.
Should this occur, there is potential for serious injury or death.
· Operate the compressor in a well ventilated area free of flammable
vapors, dust, or other combustible materials.
· Never place objects against or on top of the compressor. · Never expose the Air Oil Separator Tank or compressor to extreme
heat.
Compressor Air and Oil Hazard
· The compressor system is under sufficient pressure that a leak
could force the air/oil mixture through the skin directly into your bloodstream. This could cause serious injury or death.
· Ensure the system is completely depressurized before attempting
maintenance or repair.
· Do not use compressed air to clean off clothing or skin, compressed
air can penetrate the skin causing serious injury or death.
· Do not move or service the compressor while it is pressurized or
operating.
· Do not move the compressor by pulling on any hoses. · Components and hoses under pressure could separate suddenly, fly
out and cause serious injury or death. If equipped, the air receiver tank must be drained before servicing any components in the compressor system.
· Never adjust or attempt to make any repairs to the system while
the engine is running. Components and hoses under pressure could fail and cause serious injury or death.
Burst Hazard
· Serious injury or death may result from an air tank explosion. · Never exceed manufacturer’s maximum air pressure rating. · Do not repair components, only replace with approved parts. · Do not tamper with or disable factory safety equipment.
Moving Parts Hazard
· Before performing service, disconnect the negative battery cable
and the spark plug wire to prevent unexpected engine start.
· Do not operate the compressor without guards in place. If the
guards are damaged or missing, replace them before operating the equipment.

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General Warnings
· Ensure the compressor and hydraulic system are cool and
depressurized prior to servicing.
· Be attentive for unexplained changes in operation parameters and
record any changes.
· Check the compressor oil level and condition before starting the
system. Do not add or change oil while the system is running. Use only approved oil.
· The compressor may operate anytime the hydraulic circuit is
energized. Avoid contact with the compressor, hoses, or motor during operation.
· Keep hoses and wiring away from hot, sharp, or moving
components.
· Use only approved hoses and replacement parts. · Do not modify the equipment. · Do not operate the air compressor when fatigued or under the
influence of alcohol or drugs.
· Know how to operate the compressor, fully read the manual. · Check equipment before every use. · Never bypass or disable any of the safety equipment. · Never adjust or attempt to make any repairs to the compressor
system while the hydraulic circuit is pressurized. Components and hoses under pressure could fail and cause serious injury or death.

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Warranty

VMAC Standard Warranty (Limited)
For complete warranty information, including both VMAC Standard Warranty (Limited) and VMAC Lifetime Warranty (Limited) requirements, please refer to our current published warranty located at: www.vmacair.com/warranty

If you do not have access to a computer, please contact us and we will be happy to send you our warranty.

VMAC’s warranty is subject to change without notice.

VMAC Lifetime Warranty (Limited)

A VMAC Lifetime Limited Warranty is offered

AIR INNOVATED

on the base air compressor only and only on

UNDERHOOD, Hydraulic Driven, Transmission Mounted, Gas and Diesel Engine Driven Air

LIFETIME

Compressors, Multifunction Power Systems, and other products as defined by VMAC, provided that (i) the purchaser fully completes and submits a

WARRANTY
TRUST SERVICE VALUE

warranty registration form within 3 months of purchase, or 200 hours of operation,

whichever occurs first; (ii) services are completed in accordance with the Owner’s

Manual; (iii) proof of purchase of applicable service kits are made available to

VMAC upon request.

The VMAC Lifetime Warranty is applicable to new products shipped on or after 1 October, 2015.

Warranty Registration

The VMAC warranty registration form is located near the back of this manual. This warranty registration form must be completed and sent to VMAC at the time of installation for any subsequent warranty claim to be considered valid.

There are 4 ways the warranty can be registered with VMAC:

www.vmacair.com/warranty

warranty@vmacair.com
877-740-3202 VMAC – Vehicle Mounted Air Compressors 1333 Kipp Road, Nanaimo, BC, Canada V9X 1R3

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VMAC Warranty Claim Process
VMAC warranty work must be pre-authorized by VMAC. Claims are processed via our dealer network. If you are not a VMAC dealer, please select one to work with via our Dealer Locator: https://www.vmacair.com/dealer-locator/

1. Communicate with VMAC Technical Support at 1-888-241-2289 or tech@vmacair.com to help diagnose/troubleshoot the problem prior to repair. VMAC technical support will require the VMAC System ID, hours on the compressor and mileage on the vehicle.
2. VMAC will provide direction for repair or replacement of the failed components.
3. If requested, failed parts must be returned to VMAC for evaluation.
4. Dealers may login to the VMAC website to view the “VMAC Labour Time Guide” (under “Agreements”) to see the allowable warranty labour times.
5. Warranty invoices must include the Service Ticket number, VMAC System ID#, hours on the compressor, and a detailed description of the work performed.
6. VMAC Warranty does not cover consequential damages, overtime charges, mileage, travel time, towing/recovery, cleaning or shop supplies.
7. Dealers submit warranty claims on behalf of the Vehicle Owner/End User affected by the defective part(s). The dealer ensures that all warranty credits are refunded back to the Vehicle Owner/End User who made the initial warranty claim.
In order to qualify for Lifetime Warranty (Limited), the completed warranty registration form must be received by VMAC within 3 months of the buyer receiving the Product(s), or 200 hours of operation, whichever occurs first.
If the completed warranty registration form has not been received by VMAC within 3 months of the buyer receiving the Product(s), or 200 hours of operation, the “Standard” warranty period will be deemed to commence 30 days from the date of shipment from VMAC.
Failure to follow the warranty claim process may result in denial of the warranty claim.
VMAC Product Warranty Policies & Warranty Registration can be found on the VMAC website (see previous page for URL).

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®
Hydraulic Driven Air Compressor Installation Manual

Installation Considerations
The information in this section is critical to ensure proper operation of the system. Read these requirements prior to beginning the installation.
Failure to adhere to these recommendations will cause the Hydraulic Driven Air Compressor system to operate erratically.
Prior to installing the system, consider the following factors:
· For proper operation, VMAC’s Hydraulic Driven Air Compressor Systems require
proper hydraulic pressure and flow, ensure the hydraulic circuit is designed with these requirements in mind (see page 17).
· See “Hydraulic Fluid and Line Sizing Recommendations” on page 19 for
additional hydraulic circuit recommendations.
· Special consideration is required for variable rate hydraulic pumps
(see page 17). Is the intended location convenient for electrical, hydraulic, and air connections?
· Will the intended location require extensive plumbing for the hydraulic system
or air hoses?
· Are the wire lengths, and air/hydraulic hose lengths as short as possible, and
with the least amount of 90° fittings possible?
· Can the oil level at the sight glass be checked easily? · Can the unit be serviced easily? · Will there be adequate clearance around the unit to provide good air
circulation and effective cooling (see page 14)?
· Will the unit be protected from excessive exposure to the elements? · Will the unit be protected from incidental damage from other operations? · Will the unit be mounted away from heat sources such as engines, exhaust, or
other components that can generate heat.
· Will the unit be mounted where it will be exposed to high contamination levels,
including combustible gases?
· If the intended mounting location is constructed of thin gauge material,
consider using the VMAC Mounting Brackets (P/N: A700140).
The integrated cooler on the Hydraulic Driven Air Compressor system is capable of removing all of the heat generated during air compression from the compressor oil and hydraulic fluid.
Additional hydraulic oil cooling (such as VMAC’s Hydraulic Oil Cooler (P/N: A850001) may be required for any other hydraulic equipment installed on the same circuit.

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Mounting Locations and Ventilation
Top Mounting
“Top mounted” is the preferred mounting location for the Hydraulic Driven Air Compressor. Placing the unit on top of the service body provides the best access to cool fresh air. Maintain a minimum of 6 in between the sides of the Hydraulic Driven Air Compressor and all other solid objects (Figure 1).
VMAC does not recommend mounting the unit at the back of the vehicle as the drag created when the vehicle is moving causes debris to be deposited (and accumulated) inside the unit.
Enclosed Mounting
Enclosed mounting is not recommended due to the significant heat generated by the Hydraulic Driven Air Compressor.
Mounting the Hydraulic Driven Air Compressor in an enclosure will limit access to cool fresh air, restrict the escape of hot air from around the unit and have an adverse effect on cooling which may reduce the unit’s duty cycle. Ensure adequate ventilation is provided for cooling and to evacuate the heat generated by the unit. If mounting in an enclosure, VMAC strongly recommends mounting the unit on a pullout drawer and extending the drawer any time the unit is run.
Top mounted (Preferred)

Enclosure mounted (not recommended)

Not recommended

Figure 1 — Mounting locations
While it is not possible to make absolute recommendations regarding ventilation due to the widely differing circumstances that are possible, duty cycle, ambient temperature and enclosure shape are some of the important variables that must be considered.

Significant ventilation and additional cooling will be required if the Hydraulic Driven Air Compressor is mounted in the same enclosure as the hydraulic oil reservoir. The heat generated during operation will continue to heat the hydraulic fluid (even with fresh ambient air entering the cooler).

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Recommended Component Layout
Battery Fuse
Ignition switched
relay
Hydraulic Driven Air Compressor

Display Box (mounted inside weather
proof enclosure)

Figure 2 — Recommended component layout

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Speed Control
The Hydraulic Driven Air Compressor has the ability to signal for a higher engine speed under high air demand conditions and for a lower engine speed under low air demand conditions. A built in, electrically activated idle up system or an aftermarket product is required to provide 2 speed operation.
The Hydraulic Driven Air Compressor is capable of constant operation at a fixed engine speed and hydraulic pump gpm. There are several advantages to configuring the system for 2 speed operation:
· Lower fuel consumption. · Lower noise when air demand is low. · Lower wear rates on the engine, hydraulic pump and compressor. · Faster warm up during cold start weather.
The preferred approach for speed control is to restrict the hydraulic flow to the Hydraulic Driven Air Compressor to the minimum requirement for the system (8 ­ 9 gpm for the H40), this is desirable for cold climate start-up as it keeps hydraulic pressure low during warm up.
The system must be at, or above, the minimum hydraulic flow before starting the Hydraulic Driven Air Compressor.
Single Speed Operation (See Figure 3 on page 17 for “gpm vs cfm” chart) When the system is activated, the Control Box in the Hydraulic Driven Air Compressor will signal the PTO to increase hydraulic flow to provide the desired cfm. 2 Speed Operation (See Figure 3 on page 17 for “gpm vs cfm” chart) When the system is enabled, “Speed 1” is activated and the Control Box in the Hydraulic Driven Air Compressor will signal the PTO to set hydraulic flow to the minimum desired cfm.
“Speed 2” is activated to signal the PTO to increase hydraulic flow to provide the maximum cfm (or speed system warm up).

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Hydraulic Requirements
VMAC’s Hydraulic Driven Air Compressors are designed to be driven by fixed displacement hydraulic pumps. Hydraulic circuits using “pressure compensated” variable displacement pumps must have a Closed Centre Manifold installed at the Hydraulic Driven Air Compressor (see “Accessory Products from VMAC” on page 79). VMAC’s Hydraulic Driven Air Compressors are not compatible with “load sensing” variable displacement hydraulic pumps.
VMAC is unable to provide hydraulic circuit designs or consult on specific hydraulic installations. We recommend working with a local hydraulic expert to design and/or install the hydraulic circuit that will power the Hydraulic Driven Air Compressor system.

H40

Figure 3 — cfm vs gpm
H40
While in operation, the required system pressure will vary between 900 psi and 2,500 psi.
The hydraulic pump must be rated for 2,500 psi (steady state) and 2,900 psi (intermittent) to allow for an additional 200 psi pressure drop in the pressure lines (external to the system) during startup with cold hydraulic fluid.
The system must maintain hydraulic flow between 9 gpm and 14 gpm (Figure 3).

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The stated hydraulic flow rates are nominal values only and may change due to variations in hydraulic system efficiency, load, and flow. Tests should be performed to confirm that the desired cfm has been achieved.
If the Hydraulic Driven Air Compressor system is being installed into an existing hydraulic circuit, ensure the circuit meets the requirements listed in this chapter.
Filtration VMAC recommends that the hydraulic circuit meet or exceed ISO Code 16/13, SAE Class 4.
See “Hydraulic Fluid and Line Sizing Recommendations” on page 19 for additional information.
An independent hydraulic system is recommended to simplify installation, operation, and troubleshooting of the Hydraulic Driven Air Compressor system.
If this system is being installed in a shared hydraulic circuit, the use of a shut off valve is advised.

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Hydraulic Fluid and Line Sizing Recommendations

VMAC is unable to provide hydraulic circuit designs or consult on specific hydraulic installations. We recommend working with a local hydraulic expert to design and/or install the hydraulic circuit that will power the Hydraulic Driven Air Compressor system.
The following information is intended as a guideline only.
Climate / Temperature Reference Chart

Extreme Cold Climate

Cold Climate

Temperate Climate

Below -4 °F (-19 °C)

-3 °F — 32 °F ( -19 °C — 0 °C)

Above 32 °F (0 °)

Table 1 — Temperature reference chart

Hydraulic Fluid Type

Use only premium quality mineral or synthetic anti wear hydraulic fluid.

When selecting which hydraulic fluid to use, the decision should be based on the lowest overnight temperature that the unit will be used in.

Cold Climate

Temperate Climate

AW22

AW32

When possible change to AW32 (e.g. during summer months)

Table 2 — Hydraulic fluid chart

Mount Location Tank and Suction Line Preheat No Tank Preheat

Extreme Cold Climate AW32 A seasonal hydraulic fluid change is recommended.

Table 3 — Hydraulic fluid recommendation for extreme cold climates

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Hydraulic Line Sizing
Industrial hydraulic system design guidelines generally call for the following maximum fluid velocities, which are then used to select line sizes for any particular gpm:
· Supply 4 ft/sec. · Return 10 ft/sec. · Pressure 20 ft/sec.
The above guidelines are not considered comprehensive when working with mobile hydraulic applications on prebuilt chassis due to the following factors:
· Extreme start-up temperature variations. · Long supply lines. · Piggy- backing of motor case drain flow onto the main return line.
Hydraulic pump failure due to cavitation, and/or hydraulic motor seal failure due to excess return line pressure, may occur if the above considerations are ignored when line sizes are being determined.
The following information provides specific line sizing recommendations for mobile hydraulic system installations intended for use with VMAC’s Hydraulic Driven Air Compressor systems. The dimensions provided indicate “inside diameter” (ID). Supply Line Sizing
Failure to use the correct suction line size may result in hydraulic pump cavitation leading to premature pump failure.
In order to determine the appropriate supply line size, first identify the climate
that the system will be used in (Table 1), then select the corresponding line size based off of the maximum gpm of the system (Table 4 or Table 5 starting on page 21).
Special design considerations are required for hydraulic systems operating in extreme cold climates. VMAC recommends consulting with hydraulic experts experienced in the design and installation of hydraulic circuits that will be used in temperatures below -4 °F (-19 °C).

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gpm during start up / warm up

Supply Line Size AW 22

Up to 8 gpm

1 in (up to 1 ft) 1 1/4 in (up to 2 1/2
ft) 1 1/2 in (up to 6 ft) 1 3/4 in (up to 9 ft)
2 in (above 9 ft)

12 gpm

1 1/4 in (up to 1 1/2 ft)
1 1/2 in (up to 4 ft) 1 3/4 in (up to 6 ft)
2 in (up to 12 ft) 2 1/2 in (above 12
ft)

16 gpm

1 1/2 in (up to 3 ft) 1 3/4 in (up to 4 1/2 ft) 2 in (up to 9 ft)
2 1/2 in (above 9 ft)

21 gpm

1 1/2 in (up to 2 ft) 1 3/4 in (up to 3 1/2 ft) 2 in (up to 7 ft)
2 1/2 in (above 7 ft)

Table 4 — Cold climate

gpm during start up / warm up

Supply Line Size AW 22

Up to 8 gpm

1 in (up to 4 ft) 1 1/4 in (up to 8 ft) 1 1/2 in (above 8 ft)

12 gpm

1 1/4 in (up to 5 ft) 1 1/2 in (up to 11 ft) 1 3/4 in (above 11 ft)

16 gpm

1 1/2 in (up to 9 ft) 1 3/4 in (up to 13 ft)
2 in (above 13 ft)

Supply Line Size AW 32
1 1/4 in (up to 1 ft) 1 1/2 in (up to 2 1/2 ft) 1 3/4 in (up to 3 1/2 ft)
2 in (up to 8 ft) 2 1/2 in (above 8 ft)
1 1/2 in (up to 1 1/2 ft) 1 3/4 in (up to 2 1/2 ft)
2 in (up to 5 ft) 2 1/2 in (up to 13 ft)
3 in (above 13 ft)
1 1/2 in (up to 1 ft) 1 3/4 in (up to 2 ft)
2 in (up to 4 ft) 2 1/2 in (up to 10 ft)
3 in (above 10 ft) 1 1/2 in (up to 1 ft) 1 3/4 in (up to 1 1/2 ft)
2 in (up to 3 ft) 2 1/2 in (up to 8 ft)
3 in (above 8 ft)
Supply Line Size AW 32
1 in (up to 1 1/2 ft) 1 1/4 in (up to 4 ft) 1 1/2 in (up to 9 ft) 1 3/4 in (above 9 ft) 1 1/4 in (up to 2 1/2 ft) 1 1/2 in (up to 6 ft) 1 3/4 in (up to 9 ft)
2 in (above 9 ft) 1 1/2 in (up to 4 ft) 1 3/4 in (up to 7 ft)
2 in (up to 14 ft) 2 1/2 in (above 14 ft)

21 gpm

1 1/2 in (up to 7 ft) 1 3/4 in (up to 11 ft)
2 in (above 11 ft)

1 1/2 in (up to 2 1/2 ft) 1 3/4 in (up to 5 ft) 2 in (up to 11 ft) 2 1/2 in (above 11 ft)

Table 5 — Temperate climate

Pressure and Return Line Sizing

Pressure Line Size
3/4 in

Return Line Size
1 in

Table 6 — Pressure and return line size

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Hydraulic Driven Air Compressor Harness Reference

Colour Purple Green
Red

Installer Interface

Pin

Function

Notes

A High Idle Output

Ground switching signal, use to supply ground to relay or equivalent

B System Ground

0

C System Power

+12 V

Colour Red Green

Fan Motor

Pin

Function

A Relay Switched +12 V +12 V

B System Ground

0

Notes

Colour Red
Orange Red Red

Pin 5 (85) 2 (86) 4 (87) 1 (30)

Fan Relay

Function

Notes

System Power

+12 V

Switched Ground

Switched

Relay Switched +12 V (To fan motor) +12 V (H400003: +24 V)

System Power

+12 V (H400003: +24 V)

Colour Red Green White Black

Display Box

Pin

Function

Notes

A Display +12 V

+12 V

B Display Ground

0

C CAN Hi

CAN bus signal

D CAN Low

CAN bus signal

Colour Red Green Black

System Pressure Sensor

Pin

Function

Notes

­ +5 V

+5 V

­ Pressure Signal

+0.5 V ­ +4.5 V, 0 ­ 150 psi (ratiometric)

­ Ground

0

Colour Red Black

Air Solenoid

Pin

Function

1 +12 V Supply

+12 V

2 Switched Ground

Switched

Notes

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Colour Red Red
Colour Blue Blue
Colour Yellow
Colour White
White
Colour Orange
Orange

Hydraulic Solenoid

Pin

Function

A Switched Ground

Switched

B +12 V Supply

+12 V

Notes

Heater Solenoid (Cold Climate Kit P/N: A800070)

Pin

Function

Notes

A Switched Ground

Switched

B +12 V Supply

+12 V

Remote Switch Wire

Pin

Function

Notes

­ Remote Enable Wire Ground wire to run compressor

Compressor Temperature Probe

Pin

Function

Notes

A

Thermistor Signal Voltage

Varies with temperature – see thermistor resistance tables for further diagnosis.

B

Thermistor Signal Voltage

Varies with temperature – see thermistor resistance tables for further diagnosis.

Hydraulic Temperature Probe

Pin

Function

Notes

A

Thermistor Signal Voltage

Varies with temperature – see thermistor resistance tables for further diagnosis.

B

Thermistor Signal Voltage

Varies with temperature – see thermistor resistance tables for further diagnosis.

Table 7 — Harness reference chart

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Electrical Requirements

The information in this section is critical to ensure proper operation of the system. Read these requirements prior to beginning the installation.
Failure to adhere to these recommendations will cause the Hydraulic Driven Air Compressor system to operate erratically.

VMAC’s Hydraulic Driven Air Compressor systems require a steady 20 A at 12 V dc (nominal) to operate. A 30 A fuse or circuit breaker is recommended. To ensure an uninterrupted supply of power, the ground wire should be routed either to the negative terminal of the battery or to a substantial, fully grounded point on the vehicle chassis. Confirm the selected ground is good by using an ohm meter to measure the resistance between the ground point and the negative battery terminal. Resistance should be less than 1 .
The power supplied to the unit should be ignition switched through a relay to reduce the risk of battery drain when the engine is off. The main power should be supplied directly from the positive terminal of the battery via a relay. Using a relay allows the heavy gauge power wire to be routed directly and permits the use of a light gauge wire (e.g. 18 AWG) between the relay and the control switch.

Wire Sizing Guide

Combined length of power and ground wires Recommended wire gauge

Less than 10 ft (3 m)

12 AWG

Between 10 ft (3 m) and 18 ft (5.5 m)

10 AWG

18 ft (5.5 m) to a maximum of 35 ft (10.5 m) 8 AWG

Table 8 — Wire size table

VMAC does not recommend installing the system in a location that would require a combined wire length greater than 35 ft (10.5 m).

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Electrical Schematic

Figure 4 — Electrical schematic

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Installing the Hydraulic Driven Air Compressor System
Mounting the Unit
Remove the unit from the packaging. Ensure the (×4) rubber isolator mounts remain fastened to the base of the unit.
Some hydraulic fluid will run out of the unit when the ORB fittings are removed, ensure all environmental regulations are adhered to.
Remove the (×2) ORB plugs from the manifold on the side of the unit. Install suitable ORB fittings to connect the system to the hydraulic circuit. *Optional: If the VMAC Cold Climate Kit (P/N: A700280) is being installed, do so
now using the instructions included with the kit.
Failure to mount the unit using the rubber isolators will result in considerable noise and vibration during operation.
Remove the 3/4 in NPT plug from the AOST and install a suitable fitting to
connect it to the downstream equipment (i.e. air receiver tank, hose reel, etc.).
Mount the unit (Figure 5). · If using the VMAC Mounting Brackets (P/N: A700140), install them now. · If using the integral mounts, drill (×4) 13/32 in holes in the selected mounting
location.

Figure 5 — Mounting dimensions (in inches)
Apply Loctite 242 (blue) to the mounting studs and secure the unit in place. Connect the Hydraulic Driven Air Compressor to the hydraulic circuit.

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Testing the Installation
Ensure there are no people around the Hydraulic Driven Air Compressor prior to performing the following the test.
The VMAC supplied and approved compressor oil must be used in this system. Failure to use this special oil will result in damage to the compressor and will void the warranty. Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
Before Starting the System
Verify the compressor oil is at the correct level (the system is filled at the
factory but the level must be checked prior to operation).
Verify the hydraulic fluid is at the correct level. Perform a final inspection to ensure that all:
· Fasteners and connections are tight. · Hoses are secure and adequately protected. · Wiring is secure and adequately protected. Temporarily install a hydraulic flow meter with pressure gauge (see “Hydraulic
Testing” on page 73) into the hydraulic circuit at the supply line to the Hydraulic Driven Air Compressor to confirm actual hydraulic flow.
Install the VMAC Air Test Tool (A700152) with the appropriate orifice and the
ball valve closed.
Begin circulating hydraulic fluid.
If the unit is vehicle mounted, ensure the vehicle is parked on level ground, the transmission is in “PARK”, with the parking brake engaged and the wheels blocked.
If the ambient temperature is below -13 °F (-25 °C), circulate the hydraulic fluid to warm it prior to activating the Hydraulic Driven Air Compressor.
After Engaging the Hydraulics
Check the hydraulic circuit for leaks. Verify the hydraulic flow meets the minimum requirements for the system
installed (page 17).
Turn the Hydraulic Driven Air Compressor on. See “What to Expect at Startup”
on page 41.
On systems configured for 2 speed operation, the engine rpm should reduce to the second speed once full system pressure is achieved (factory default: 150 psi).

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Always allow for efficiency loss as the hydraulic fluid heats up and adjust the gpm as required to ensure that the flow delivered at “Speed 1” does not drop below the minimum requirement.
Open the ball valve on the VMAC Air Test Tool (if not using the VMAC Air test
tool with the proper orifice, open the ball valve enough to maintain 100 psi) and operate the system for at least 1 hour at full load while monitoring the hydraulic flow and cfm output.
Close the ball valve and allow the system to build to full system pressure. Turn the Hydraulic Driven Air Compressor off and allow the system to cool. Check the compressor oil level after the oil level has had time to stabilize. Check the hydraulic fluid level after the system has been shut down. Remove the Hydraulic test tool from the system. Restart the system and verify there are no leaks in the area where the hydraulic
test tool was installed.

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Performance Testing and System Adjustments

The cfm generated by the Hydraulic Driven Air Compressor is dependent upon the gpm delivered by the hydraulic circuit. The following test requires that the hydraulic circuit delivers the maximum gpm for the Hydraulic Driven Air Compressor model installed.
Ensure any other hydraulic equipment installed on the circuit is either rated to accept the maximum hydraulic flow, or is adequately protected during testing (see “Hydraulic Requirements” on page 17).
Compressor Performance Testing
System operation can be tested using the tools that will be operated by the system or by using the VMAC Test Tool (A700052) with the appropriate orifice in the outlet to simulate tool use (Figure 6).

JIC Adapters

Orifice

Ball valve

Install orifice here
Figure 6 — A700052 VMAC Air Test Tool
Disconnect all downstream equipment (hose reels, etc.) and connect the test tool directly to the discharge fitting on the AOST.
Ensure there are no leaks in the test tool. The system may not idle down if there are leaks in the lines or fittings.
Install the VMAC test tool at the AOST outlet with the appropriate orifice. Ensure the ball valve is closed. Start the system. See “What to Expect at Startup” on page 41 for more
information.
Ensure the system has reached normal operating temperature and is no longer
in “Soft Start”.
Observe the pressure gauge on the test tool. The pressure should be
approximately 150 psi.
Open the ball valve on the test tool completely and observe the pressure
gauge.

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If the system is not able to maintain air pressure at 90 psi when the ball valve is fully opened, the compressor has failed the performance test.
Close the ball valve slowly to allow the system pressure to rise. When the pressure reaches 150 psi (factory default setting), the system will
“unload” and air should be heard to escape from the inlet. Systems configured for 2 speed operation will reduce flow to maintain the minimum gpm.
After 1 minute without air use (factory setting), the hydraulic fluid will continue to circulate through the cooler but the compressor will stop turning. The system will continue to monitor the temperature of the hydraulic fluid and will activate the cooling fan as required.
The system will continue to monitor temperature and air pressure and will restart as needed to maintain operating parameters.

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®
Hydraulic Driven Air Compressor Owner’s Manual

Identifying Your System
The System ID will be requested any time that parts are ordered, when calling for technical support, or submitting a warranty claim.
The system ID is the preferred method of identifying the system as it serves as a master record of all of the components in the system. The system ID plate is generally found on the top cover of the Hydraulic Driven Air Compressor (Figure 7).

Figure 7 — System ID location
An alternative method of identifying the system is via the compressor serial number which is found on a plate attached to the compressor. This is a less desirable method of identifying the system as it may not link back to the original system if it has been replaced.
System ID breakdown
The system ID provides specific information about the system such as the model, revision, production date and the unique identifier (Figure 8).

Model number

Unique identifier

Revision letter

Production date code

Figure 8 — System ID breakdown

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System Components and Specifications

Components

The Hydraulic Driven Air Compressor system consists of the following components:

· Air Oil Separator Tank (AOST). · Compressor. · Hoses and tubes. · PTFE oil scavenge and pressure
control tubes. · Digital Display Box.
AOST

· Liquid to air cooler. · Hydraulic manifold. · Air solenoid. · Control box.

Air/oil discharge from
compressor

Oil sight glass

Oil filter

Oil supply to compressor

Figure 9 — AOST (front)

Oil drain
3/16 in pressure control fitting

Pressure sensor

Blowdown muffler

200 psi pressure relief valve
1/4 in oil scavenge fitting

3/4 in NPT to JIC adaptor (not included)

Figure 10 — AOST blowdown cap (back)

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Compressor Oil supply
Temperature sensor

Air filter

Hydraulic fluid return (on back of hydraulic motor)

Air/oil discharge
Liquid to Air Cooler

Inlet valve

Hydraulic motor

Figure 11 — Compressor assembly

Cooled hydraulic fluid (return line)

Hydraulic fluid supply

Hot hydraulic fluid (from compressor)

Electric Fan

Cool oil to compressor

Hot compressor oil from AOST

Liquid to air cooler

Figure 12 — Compressor oil / hydraulic fluid cooler

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Hydraulic Manifold
Hydraulic fluid from compressor

Hydraulic fluid to cooler

Hydraulic fluid solenoid
Hydraulic pressure relief valve

Cooled hydraulic fluid (return to hydraulic circuit)
Hydraulic fluid case drain
(from motor)

Hydraulic fluid temperature
sensor

Control Box

Figure 13 — Hydraulic manifold

Hydraulic fluid to compressor

Control box

Figure 14 — Control box

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Air Solenoid

Air solenoid

Figure 15 — Air solenoid

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Digital Display Box The Control Box serves as the operator’s control panel and contains the “” (back) and “” (forward) buttons, “READY” and “WARNING” lights, and the display LED which includes information such as compressor hours, service reminder, warning messages, error codes, access to the advanced settings, and diagnostic information.
Display LED

Back button

Status lights
Figure 16 — Control Box

Forward button

Hoses / Tubes
The hoses used in VMAC compressor systems have an AQP inner liner that is compatible with VMAC compressor oil. The PTFE tubes used in VMAC systems are rated for the high temperatures VMAC compressors generate. Use of hoses or tubes other than those supplied or recommended by VMAC may cause compressor damage and may void your warranty. Please contact VMAC for replacement hoses/tubes or for further information.
· Hoses must have an AQP liner. · Oil scavenge and pressure control tubes must be PTFE.

VMAC Compressor oil will degrade rubber lined hoses, use only hoses with an AQP elastomer type liner. Contact VMAC Technical Support at 1-888-241-2289 for further information.

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Specifications
This system is designed to be driven by a fixed displacement hydraulic pump.
This system is compatible with “pressure compensated” variable displacement pumps when the VMAC Closed Centre Manifold (P/N: A700190) is installed (see “Accessory Products from VMAC” on page 79).
This system is not compatible with “load sensing” variable displacement hydraulic pumps.
Air Compression Our Hydraulic Driven Air Compressors use a VMAC designed and manufactured flooded lobe, rotary screw compressor. The oil filled compressor housing contains 2 rotors. Compression occurs when air (at normal atmospheric pressure) enters a chamber where it is trapped between meshing rotor lobes. Cooled oil is injected into the rotors during compression to lubricate the rotors and bearings, absorb the heat of compression, and seal the rotor lobes to allow for efficient compression. As the rotors rotate, the meshing lobes compress the volume of the trapped air/oil mixture before sending it down the discharge line to be cooled and separated by the Air Oil Separator Tank (AOST).
Oil Separation The system uses a proprietary 2 stage air/oil separator. The hot air/oil mixture from the compressor enters the first stage of the AOST and is mechanically separated with baffles. The second stage uses an integral coalescing element to remove the remainder of the oil from the air stream.
The small amount of oil recovered from the coalescing filter is returned directly to the compressor via the 1/4 in PTFE scavenge tube.
Compressor Oil and Hydraulic Fluid Cooling A liquid-to-air cooler maintains operating temperatures in an optimal performance range which increases system durability and reduces the temperature of the compressed air.
Hot compressor oil is directed from the AOST to VMAC’s liquid to air cooler before being returned to the compressor. The liquid to air cooler also cools the hydraulic fluid to ensure the Hydraulic Driven Air Compressor does not add heat to the hydraulic circuit.
Filtration VMAC rotary screw compressors are designed and machined to exacting standards. Foreign particles entering the compressor can damage components such as rotors, bearings, seals, and the housing, resulting in performance, efficiency loss, and reduced system life.
The system is equipped with a replaceable paper element air filter, a high pressure spin-on oil filter, scavenge screen and a coalescing filter in the back of the AOST.

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Pressure Regulation Pressure regulation is achieved via a mechanical inlet control valve and an electric air solenoid.
The system pressure is set at the factory to 150 psi. Pressure can be adjusted between 110 psi and 150 psi by using the display box. To reduce the operating pressure, VMAC recommends using an Filter Regulator Lubricator (FRL) (P/N: A700151). Refer to “Accessory Products from VMAC” on page 79.
Safety Features A 200 psi (1380 kPa) pressure relief valve is installed in the AOST to prevent over pressurization. The AOST is also equipped with an integrated rapid blow down system that automatically discharges pressure from the AOST upon shutdown.
Temperature sensors are installed in the compressor and the hydraulic manifold. In the event that the air/oil, or hydraulic temperature increases above a safe level, the system will deenergise the hydraulic solenoid, stopping the compressor. The red “WARNING” light on the Display Box will illuminate and the error will be logged in the system.
H40
· 2,800 psi hydraulic pressure relief valve.
Table 9 — Hydraulic pressure relieve valve values

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System Operation (What to Expect at Start Up)
Before Running the Hydraulic Driven Air Compressor:
· Ensure the system is not mounted (or parked) on grades exceeding 15° as this
will affect lubrication and air/oil separation (Figure 17).

Figure 17 — Do not exceed 15° grade
If installed inside a cabinet or enclosure, open the cover or door completely and secure it in the open position to provide proper ventilation.
Startup Procedure
If equipped, open the hydraulic shutoff valve. Check the compressor oil level at the sight glass in the AOST. Check the hydraulic fluid level in the hydraulic system tank. Engage the hydraulic system. Turn on the Hydraulic Driven Air Compressor via the vehicle’s control panel. Watch the display box for system status information.
What to Expect at Startup
If installed, the VMAC Cold Climate Kit (P/N: A700280) will automatically activate in cold weather.

The Hydraulic Driven Air Compressor will not generate full system pressure (150 psi) until both the hydraulic fluid and compressor oil are at operating temperature.
The green light on the display box will illuminate. The display box will indicate the current operating mode (Table 10 on page 42). The “” (back) and “” (forward) buttons can be used to display the hydraulic fluid or compressor oil temperatures

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Mode

Hyd. Fluid Compressor Max Temperature Temperature Pressure

Description

HYD OIL TOO COLD

Below -13 °F / -25 °C

—

0 psi.

Too cold for hydraulic oil heater

HYD OIL WARMING, -13 °F — 5 °F /

HYD xxxF/xxxC

-25 °C — -15 °C

—

0 psi

Throttle is elevated. Hydraulic oil heater accessory enabled (if equipped).

SOFT START xxC

5 °F — 41 °F / -15 °C — 5 °C

Below 90 °F / 32 °C

Up to 40 psi

Throttle is elevated. Compressor is ON. Compressor oil is warming.

120 PSI MAX 120 PSI MAX Various

5 °F — 41 °F / -15 °C — 5 °C

Above 90 °F / 32 °C

Above 41 °F / 5 °C

Above 59 °F / 15 °C

Above 41 °F / 5 °C

Above 113 °F / 45 °C

120 psi 120 psi 150 psi

Winter start. Throttle is elevated. Compressor is ON. Pressure is limited for warm up. Full cfm output.
Spring start. Throttle is elevated. Compressor is ON. Pressure is limited for warm up. Full cfm output.
Throttle is elevated. Compressor is ON. Full air pressure and cfm output

Table 10 — System performance chart
The control box will enable/disable the cooling fan as needed to keep the hydraulic fluid and compressor oil within normal operating temperatures (Table 11).

Condition
· Comp oil above 190 °F / 88 °C. OR
· Comp oil above 170 °F / 77 °C and hydraulic fluid above 151 °F / 66 °C.
· Comp oil below 161 °F / 72 °C. OR
· Comp oil below 170 °F / 77 °C and hydraulic fluid below 122 °F / 50 °C.
Table 11 — Cooling fan temperature triggers

Fan Status
On Off

Normal Operation
Once the system reaches “normal operating temperature” (compressor temperature: 113 °F (45 °C) / hydraulic fluid: 41 °F (5 °C)), the system will build to full system pressure (150 psi) and maximum cfm (the cfm that the system develops is dependent upon hydraulic fluid gpm ­ see “Hydraulic Requirements” on page 17).

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During normal operation, the Hydraulic Driven Air Compressor monitors various parameters including compressor temperature, hydraulic fluid temperature, and air pressure.
When no air use is detected, the system will first unload the compressor and then enter “Standby” to minimize fuel consumption, equipment wear, hydraulic and compressor temperature, and noise.
System Unload Once the system has built to 150 psi, the compressor will “unload”. If the engine speed had increased, it will drop to base rpm to “unload” the hydraulic system.
A hissing sound may be heard near the inlet valve as excess air is released to reduce pressure inside the compressor to approximately 40 psi.
If no air use is detected after 2 minutes (pressure in the AOST remains above the restart point (factory default: 120 psi), the system will enter “Standby”.
System Standby
Once in “Standby”, the hydraulic motor will turn off and “STANDBY xxx PSI” will show on the display. The delay to standby time and restart pressure is adjustable, (see page 48).
As stored air is used and the pressure drops below the configured restart pressure, the sequence of “load up” and “unload” will repeat, (if the system is configured for 2 speed operation, engine speed will increase and drop accordingly). The system may restart occasionally (even without air use) to maintain the correct compressor and hydraulic fluid operating temperatures.
In order for the “Standby” feature to operate efficiently, the use of an air receiver tank is strongly recommended as it will reduce cycling between “load” and “unload” modes.
Shut-down

1. When air is no longer required, allow the system to build to full system pressure (150 psi) and unload.
2. Stop the Hydraulic Driven Air Compressor via the vehicle’s control panel. Any residual pressure in the compressor or AOST will blow-down automatically.
3. Disengage the hydraulic system.
4. If equipped, close the hydraulic shut-off valve.
5. Turn off the power supply to the Hydraulic Driven Air Compressor.
6. Drain any stored air.

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Cold or Hot Weather Operation
The compressor will not start until the hydraulic fluid temperature reaches 5 °F (-15 °C). Special design considerations are required for systems that will be used in cold climates.
Refer to the installation section for detailed information.
Hydraulic Fluid
Use hydraulic fluid that is correctly rated for the operational temperature range of the equipment.
Cold Weather Operation
When operating in cold temperatures, the following precautions should be observed:
· If the ambient temperature is below 41 °F (5 °C), cover the Hydraulic Driven
Air Compressor during transit (if exposed) and preheat the unit by circulating hydraulic fluid through the system before starting the compressor.
· If the ambient temperature is below 5 °F (-15 °C), install the VMAC Cold
Climate Kit (P/N: A700280) and circulate the hydraulic fluid through the system.
· Do not allow ice or snow to build up around the air filter and inlet control valve.
Hot Weather Operation
When operating in hot temperatures, the following precautions should be observed:
· If the ambient temperature is above 100 °F (38 °C), reduce the compressor
duty cycle.
· Provide additional hydraulic fluid cooling. The VMAC Hydraulic Oil Cooler
(P/N: A850001) is able to remove 18,750 BTU/Hr with a 50 °F (10 °C) difference in temperature between the hydraulic fluid and ambient temperature.
· Provide additional ventilation if the compressor is inside a cabinet or enclosure.
Cool air results in better performance and higher cfm (see page 14).
Automatic Shutdown
If the compressor or hydraulic fluid gets too hot, the over temperature circuit will disengage the hydraulic system, illuminate the red LED on the display box, and the display box will show a message identifying the problem.

1. Shut down the compressor. 2) Allow a few minutes for the air system to vent pressure and for the oil to drain
   back to the tank. Check the compressor oil level through the sight glass on the AOST (the oil level must be checked with the vehicle level). If the oil level is low, add VMAC compressor oil until the correct level is reached (see page 54). 3) Check the hydraulic fluid level. If necessary, add hydraulic fluid until the correct level is reached.
   If this problem persists, refer to the troubleshooting section in this manual (starting on page 65).

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Display Box Messages
The display box presents various context specific messages such as: service reminders, error messages, or the current state (e.g. “SOFT START xxxC”).
System Check
The display will show “VMAC — WWW.VMACAIR.COM” and both the red and green LED lights will flash.
The display will then show “SYSTEM CHECK / SYSTEM READY” and the system will go to the “Ready State”.
Ready State
The display will scroll through the following messages: VMAC PH# 250 740 3200 HRS: xxxx:xx
The following additional messages may be displayed at this time
500 hour service is due: “HRS: xxxx:xx 500S”
If the hydraulic fluid temperature is below -13 °F (­25 °C): “HYD OIL TOO COLD”
Every 100 hrs the system will remind the operator. “CHECK AIR FILTER”
Initial Startup (see page 41)
During initial startup, the display may show the following messages:
“SOFT START xxxC” The system has started but the compressor oil is too cold. The compressor is in “unload” mode and will only build to 40 psi.
“HYD OIL TOO COLD” The hydraulic fluid is below -13 °F (-25 °C), and the system is cautioning the operator to preheat the hydraulic fluid (the system will not start until the hydraulic fluid is above -13 °F (-25 °C)).
“HYD OIL WARMING, HYD xxxF/xxxC” The hydraulic fluid is between -11 °F (-24 °C) and +5 °F (-15 °C). If installed, the VMAC Cold Climate Kit will turn on to help warm the hydraulic fluid.
The Hydraulic Driven Air Compressor will not start until the hydraulic fluid has warmed to 5 °F (-15 °C).
Normal Operation
The system pressure, compressor oil and hydraulic fluid temperatures can be viewed by pressing the “” button while the system is running (use the “” button to scroll through the different messages). xxxPSI/xxxKPA COMP xxxF/xxxC HYD xxxF/xxxC HRS:xxxx:xx

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Standby
The following message will be displayed once the system enters Standby mode. “STANDBY xxxPSI”
While the system is in standby the hydraulic solenoid is off and the system is monitoring air pressure as well as compressor and hydraulic fluid temperatures. If the air pressure drops below the restart pressure (factory default: 120 psi), or the compressor oil temperature drops below 90 °F (32 °C), or the hydraulic oil drops below 5 °F (-15 °C), the hydraulic solenoid will energize and the system will build to 150 psi.
Error Messages
Refer to “Diagnostics and Troubleshooting” on page 65 for more information.
“OVER TEMP COMP” The compressor is too hot.
“OVER TEMP HYD” The hydraulic fluid is too hot.
“COMP PROBE SHORT” The compressor temperature probe has failed in a shorted condition.
“COMP PROBE OPEN” The compressor temperature probe has failed in an open condition.
“HYD PROBE SHORT” The hydraulic fluid temperature probe has failed in a shorted condition.
“HYD PROBE OPEN” The hydraulic fluid temperature probe has failed in an open condition.
“BATTERY LOW” The control box has sensed a low supply voltage.
“PRESSURE SENSOR?” The pressure sensor has failed or is disconnected.
“CONNECTION ERR” There is a connection problem between the control box in the Hydraulic Driven Air Compressor and the display box.

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System Adjustments (Diagnostics Mode)
Diagnostics Mode provides access to various features such as error logs, user adjustable settings, service logs, and “Limp Mode”.
Entering DIAGNOSTICS mode
With the system off: 1. Push and hold the “” button for 5 seconds.
The display will show “DIAGNOSTICS”. 2. Release the “” button.
The system will slowly scroll through the menu headings.
Entering a submenu When the desired submenu is displayed: 1. Press and hold the “” button.
Once the system has entered the desired submenu: 2. Release the “” button.
Scrolling While in a submenu, scroll through the data and variables using the “” and “” buttons.
Exiting a submenu Once changes have been made, press and hold both the “” and “” buttons at the same time. The system will return to the main diagnostics menu.
Exiting DIAGNOSTICS mode While DIAGNOSTICS is displayed, press and hold both the “” and “” buttons at the same time or power down the Hydraulic Driven Air Compressor.
Submenus
The following submenu items are accessed via the DIAGNOSTICS menu:
ERROR LOG (Figure 18) Record of the last 10 system errors.
This information can be recorded on the VMAC troubleshooting form on page 82 and emailed to VMAC Technical Support to assist in troubleshooting issues. Scroll through the errors using the “” and “” buttons.

Figure 18 — Error log display
SERVICE LOG Clears the service message and records the system hours when the last 10 system service reminders were cleared.
If the display has been showing a reminder for the 500 hour service, once the service has been completed, enter this section and clear the message.

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500HR CLEAR? Press and hold the “” button for 5 seconds to clear the message. Scroll through each recorded service using the “” and “” buttons.
AIR TEMP. SENSOR This setting provides a temporary override (“limp mode”) of the air temperature sensor at the compressor discharge. See “Limp Mode” on page 49 for more information.
HYD TEMP. SENSOR This setting provides a temporary override (“limp mode”) of the hydraulic temperature sensor at the hydraulic manifold. See “Limp Mode” on page 49 for more information.
SYSTEM PRESSURE Used to adjust the maximum system pressure. The configurable range is: 110 psi to 150 psi (factory default is 150 psi).
For optimum performance, leave the system set at 150 psi and use a regulator to reduce downstream air pressure.
Press and hold the “” button for 2 seconds, the display will show: “ADJ OFF PRES xxx” (“xxx” represents the current pressure setting in psi). Press and hold the “” and “” buttons at the same time to save the setting.
RESTART PRESSURE Used to adjust the system restart pressure. The configurable range is: 80 psi to 120 psi. This setting is limited to 30 psi (or greater) below the “UNLOAD PRESSURE” (factory default is 120 psi). Press and hold the “” button for 2 seconds, the display will show: “ADJ ON PRES xxx” (“xxx” represents the current pressure setting in psi). Press and hold the “” and “” buttons at the same time to save the setting.
DELAY TO STANDBY Used to adjust the time delay before the system goes into “STANDBY”. The configurable settings are 30 seconds, 45 seconds, 1 minute, 2 minutes, 5 minutes, 10 minutes, 15 minutes, 30 minutes and Never (factory default is 2 minutes). Press and hold the “” and “” buttons at the same time to save the setting.
COLD START LOG This is a record of the last 10 cold start temperatures (below 32 °F (0 °C).
This information can be recorded on the VMAC troubleshooting form on page 82 and emailed to VMAC to assist in troubleshooting any issues. Scroll through the cold start log using the “” and “” buttons.

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Limp Mode
Limp mode should only be used in an emergency to complete a job when servicing the unit is not immediately possible.
Running the system without an air or hydraulic temperature sensor may result in failure of the unit and/or damage to the hydraulic system, and is not recommended.
While in “limp mode”, the display box will show “NO TEMP. PROBE?” and the red LED will illuminate, then “CHECK OIL”, and the green LED will illuminate, followed by “xxxx:xx” (system hours).
While in “limp mode”, the display box will toggle between the messages approx every second. During this time, the hydraulic solenoid will be energized for 1 minute to allow the system to build pressure, then deenergized for 1 minute. When the system is turned off, “Limp mode” will be disabled and the system will operate normally. The system will need to be placed back into “Limp Mode” any time the unit it turned off until the issue is corrected. “Limp mode” is accessed via the “DIAGNOSTICS” menu. AIR TEMP. SENSOR
To temporarily disable the air temperature sensor (located beside the compressor): 1. Press and hold the “” button for 2 seconds.
The display will show: “NO AIR TEMP PRB?” 2. Press and hold the “” button for 5 seconds.
The display will show: “TEMP PROBE DIS” indicating that the air temperature sensor at the compressor discharge has been disabled.
To enable the air temperature probe: 1. Press and hold the “” button for 5 seconds.
The display will show: “TEMP PROBE EN” indicating that air temperature sensor at the compressor discharge has been enabled. HYD TEMP. SENSOR
To temporarily disable the hydraulic temperature sensor (located in the manifold). 1. Press and hold the “” button for 2 seconds.
The display will show: “NO HYD TEMP PRB?” 2. Press and hold the “” button for 5 seconds.
The display will show: “TEMP PROBE DIS” indicating that the hydraulic temperature sensor in the manifold has been disabled.
To enable the hydraulic temperature probe: 1. Press and hold the “” button for 5 seconds.
The display will show: “TEMP PROBE EN” indicating that the hydraulic temperature sensor in the manifold has been enabled.

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General Maintenance Information
Routine Maintenance
In order to maintain the VMAC warranty, VMAC’s maintenance schedule must be followed. Only genuine VMAC parts can be used to maintain the system.
With proper maintenance, the likelihood of premature failure or component replacement can be drastically reduced.
The most critical aspect of maintenance is proper air filtration, clean oil, and regular use. If any particles enter the compressor, they can score the rotors and contaminate the roller bearings in the compressor. Any contamination will cause rapid and severe damage to components.

The Hydraulic Driven Air Compressor must be run a minimum of once every 30 days for at least 30 minutes to prevent impact damage and premature bearing failure in the compressor due to vibration. Regularly running the system will also help to vaporize and exhaust any water that has condensed and accumulated in the AOST.

Torque Specifications
All fasteners must be torqued to specifications. Use manufacturers’ torque values for OEM fasteners.
The torque values supplied in Table 12 are intended for VMAC supplied components, or for use in the absence of a torque value provided by the OEM.
Apply Loctite 242 (blue) or equivalent on all engine mounted fasteners. Torque values are with Loctite applied unless otherwise specified.

Standard Grade 8 National Coarse Thread

Size

1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4

Foot pounds (ft·lb)

9

18

35

55

80

110 170 280

Newton meter (N·m)

12

24

47

74

108

149 230 379

Standard Grade 8 National Fine Thread

Size

3/8

7/16

1/2

5/8

3/4

Foot pounds (ft·lb)

40

60

90

180

320

Newton meter (N·m)

54

81

122

244

434

Metric Class 10.9

Size

M6

M8

M10

M12

M14

M16

Foot pounds (ft·lb)

4.5

19

41

69

104

174

Newton meter (N·m)

6

25

55

93

Table 12 — Torque Table

141

236

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Installation Manuals and Illustrated Parts Lists (IPL)
The installation manual and illustrated parts list are an invaluable resource when inspecting, diagnosing or repairing the system. The installation manuals and IPL’s are available free of charge from VMAC.
VMAC Installation Manuals
https://www.vmacair.com/support/manuals/

VMAC IPL’s
https://www.vmacair.com/support/ipl/

Push-To-Connect Fittings (Figure 19)
Lubricate the tube and firmly push it into the fitting so that the tube fully seats
in the fitting.
Slide the collet out, away from the body of the fitting to lock the tubing in place.
Ensure the tube does not have any “play” to prevent the O-ring from wearing.

Cut the tube square. Do not use side cutters as they will deform the tube

Slide the collet out once the tube is fully inserted

O-ring

Figure 19 — Push-to-connect fittings and PTFE tubes

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Maintenance and Repair Safety
It is impossible to warn of all the possible hazards that may result from operating, servicing, or repairing this system. Wear all appropriate Personal Protective Equipment and follow all industry standard safety practices.
Prior to performing any service, ensure the vehicle transmission is in “PARK” with the parking brake applied and the wheels chocked (if applicable).
Confirm that the system is depressurized and has cooled prior to performing any service work.
Never use flammable solvents to clean any components. If a flammable solvent has been used, rinse the component thoroughly with water and dry it before reinstalling it to prevent the possibility of explosion.
Use only genuine VMAC parts to maintain the system. Genuine VMAC parts are designed to work with the high pressure and heat generated by the compressor. Substituting genuine VMAC parts may void the warranty and could cause equipment damage, injury, or death.
This information is intended for people with mechanical trade certification who have the tools and equipment to properly and safely perform the service or repair. Do not attempt to service or repair this system without the appropriate mechanical training, knowledge and experience. Follow all safety precautions and industry standard “best practices”.
Safety Check List
Open the ball valve or connect an air tool to the system to ensure all the stored
air is released.
Gently pull up on the ring on the pressure relief valve to confirm the system is
depressurized.
Do not use the pressure relief valve as a means of depressurizing the compressor system. Doing so will prematurely wear the internal spring or the seat, preventing the valve from maintaining normal system pressure.

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Maintenance Schedule
The following maintenance schedule must be observed to maintain both the “Standard” and “Lifetime” VMAC warranties and to assure proper performance and long service life of the system. In the event of a warranty claim, VMAC may request service records.
The hours indicated are those displayed on the Control Box. Service should be performed at the lesser of the two intervals (whichever occurs first).
To order service kits, see the ordering information on page 3.

In order to maintain the warranty on the Hydraulic Driven Air Compressor, use only genuine VMAC parts to service the system.

Check the Illustrated Parts List for replacement part numbers or contact VMAC for more information.

Daily

· Check compressor oil level. · Check system for leaks.

· Check pressure relief valve condition.

Every 500 hours or 1 year (whichever occurs first)

· Change compressor air filter. · Change compressor oil. · Change compressor oil filter.

· Change pressure relief valve. · Change coalescing filter element. · Change blowdown muffler.

Service Kit Contents

500 Hour / 1 Year Service Kit P/N: A700156

QTY Part #

Description

1 3600037 Air filter

1 9200039 Oil filter

1 A700094 VMAC High performance oil (4 L)

1 A700152 Coalescing assembly

1 3600064 AOST Tank seal

1 3600090 Thimble screen

1 5840069 SPRING, COMPRESSION, FL 1.5″,OD .54

1 5830066 O-RING, VITON, 4 3/4 ID X 1/8

1 4400631 Next service due decal

Heavy Duty Air Filter Replacement Cartridge for A700136 and A700138
(optional equipment, not included in P/N: A700156)

QTY Part #

Description

1 9500061 Air filter (heavy duty air filter)

Table 13 — Service kit contents

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Regular Inspection Instructions
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 52). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
The VMAC supplied and approved compressor oil must be used in this system. Failure to use this special oil will result in damage to the compressor and will void warranty.
Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
Inspecting and Adding Compressor Oil
Ensure the unit is level and that the compressor system is depressurized and
cool to the touch.
Check the oil level in the sight glass and ensure that it is between the “MAX”
arrow and the “ADD” arrow. If the level is below the “ADD” mark, perform the following steps:
Remove the fill cap (Figure 20). Using a funnel, pour oil into the fill fitting until the oil level in the sight glass
reaches the “MAX” arrow.
A 45° #12 ORB fitting can be used to extend the fill port and ease oil filling.
Replace the fill cap and tighten securely.

Oil fill cap

Oil sight glass

Figure 20 — Inspecting the oil

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Inspecting and Replacing the Blowdown Muffler
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 52). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
The Blowdown Muffler is a regular service item and must be replaced every 500 hours or 1 year, whichever interval occurs first. Visually inspect the blowdown muffler for evidence of corrosion or loss of functionality. Ensure the muffler allows the system to depressurize. To test the blowdown system and muffler:
Turn the system on and allow it reach full system pressure (factory setting
150 psi).
Turn off the system. Listen for the pressurized air to blowdown through the muffler on the AOST.
Blowdown should be completed in approximately 20 seconds.
If the muffler is showing signs of blockage, contact a local VMAC dealer for a
replacement.
A replacement blowdown muffler is included with the VMAC 500 hour service kit.
Blowdown muffler

Figure 21 — Blowdown muffler

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Inspecting and Replacing the Pressure Relief Valve
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 52). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
Do not use the pressure relief valve as a means of releasing pressure from the system. Doing so will prematurely wear the internal spring or the seat, preventing the valve from maintaining normal system pressure. The Pressure Relief Valve is a regular service item, and must be replaced every 500 hours or 1 year, whichever interval occurs first.
Visually inspect the valve and ensure it is not corroded and that the vent holes
are not plugged.
Turn the system on and allow it reach full system pressure (factory setting
150 psi).
Ensure that air does not leak out of the valve. Air leaking from the pressure
relief valve when system pressure is at or below 150 psi indicates that the spring or seat in the valve is worn and the valve must be replaced.
If the pressure relief valve is showing loss of functionality, contact a local VMAC
dealer for a replacement.
A replacement pressure relief valve is included with the VMAC 500 hour service kit.
200 psi pressure relief
valve

Figure 22 — Pressure relief valve

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Replacing the Air Filter
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 52). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
To avoid any possibility of contamination, ensure the air inlet is covered with masking tape or a clean cloth whenever the air filter cover is removed.
Do not attempt to clean the filter element, or use compressed air to perform any tasks around the compressor until the filter and cover are replaced.
Clean any loose debris from around the compressor and the air filter cover to
prevent any contamination from entering the system.
Remove the filter cover retaining nut, filter cover and the filter element. On
some installations, it may be necessary to remove the filter assembly from the filter bracket to access the filter cover nut and remove the cover.
Immediately cover the air inlet opening with masking tape or a clean cloth to
prevent any contamination from entering the system.
Clean the inside of the filter cover with a clean, dry cloth. Remove the cloth or masking tape from the air inlet and install the new air filter
element.
Ensure the filter element fits over the “step” on the filter plate (Figure 23)
Filter plate “step”

Figure 23 — Install air filter element
Replace the air filter cover and secure it with the cover nut. Do not over tighten the nut. If removed for service, reinstall the filter onto the filter bracket.

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500 Hour / 1 Year Service
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 52). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices. Do not use compressed air or perform any other tasks around the air filter and cover until both are replaced. Never clean the filter element with compressed air as this may allow contaminants to enter the compressor system. Always replace the air filter element during this service.
Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
Apply thread sealant and replace the blowdown muffler (page 55). Apply thread sealant and replace the pressure relief valve (page 56). Replace the air filter (page 57). Clean the area around the AOST and the oil filter to prevent contamination. Slide a thin drip tray or absorbent material under the filter to collect oil spills. Remove the oil drain plug and drain the oil into a container with a capacity of
at least 6 L (1.6 USG) (Figure 24).
Oil filter
Oil drain plug

Figure 24 — Compressor oil filter
Inspect the Viton® O-ring on the oil drain plug for damage, hardness or defects
and replace if necessary.
Install and tighten the oil drain plug. Remove the oil filter (Figure 24).

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Ensure the threaded nipple did not unscrew with the oil filter. If the nipple came out with the oil filter, remove it from the filter, being careful
to avoid damaging the threads.
To reinstall the nipple, thoroughly clean the threads and apply Loctite 242 (blue)
to the end with the short threads and replace it in the AOST (Figure 24).
Clean the gasket sealing surface on the front of the AOST and inspect it for
damage. The surface must be free of old gasket material and smooth to ensure a good seal (Figure 25).
Oil filter nipple (Insert shorter threaded end into AOST)

Inspect sealing surface

Figure 25 — Compressor oil filter
Apply a thin coat of compressor oil to the rubber gasket on the oil filter. Spin the filter onto the threaded nipple until the gasket contacts the sealing
surface on the tank, then tighten the filter an additional 3/4 to 1 turn to seat the gasket.
Clean the blowdown cap at the rear of the AOST to prevent contamination. Remove the PTFE scavenge and system pressure tubes from the blowdown cap
(see page 51) and the air outlet hose. Carefully move the scavenge and system pressure tubes out of the way, ensuring that they do not twist or kink. Cap the air outlet and PTFE fittings to prevent contamination.
The coalescing separator element is spring-loaded against the blowdown cap; to prevent damage to the AOST, remove all of the bolts completely while holding the blowdown cap firmly in place.
Remove the bolts retaining the blowdown cap. Unscrew the bolts evenly to
avoid damaging the blowdown cap as the coalescing element is spring-loaded against the inside of the end cap.

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Remove the blowdown cap. Remove the Viton O-ring, coalescing element and wave spring from the AOST
(Figure 26).

Figure 26 — Replacing the Coalescing filter spring
Remove the small spring and scavenge screen. The screen can be removed by
carefully pushing it out of the oil scavenge hole from the inside of the AOST (Figure 27).

Figure 27 — Remove small spring and scavenge screen

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Wipe out the inside of the AOST. Install the new thimble screen and spring (Figure 28).

Figure 28 — Install scavenge screen and spring
Install the wave spring onto the coalescing element (Figure 29).
Wave spring

Figure 29 — Install wave spring
In addition to keeping the coalescing filter properly seated, the wave spring also prevents electrostatic buildup by grounding the coalescing filter. Failure to install the wave spring may cause an electric arc which could result in an explosion, tank rupture or fire.

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Install the coalescing element into the AOST (Figure 30).

Figure 30 — Install wave spring
Install the Blowdown cap seal in the blowdown cap (Figure 31).
Blowdown cap seal

Figure 31 — Rear cap seal

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Install the blowdown cap Viton O-ring in the AOST (Figure 32).

Figure 32 — Blowdown cap O-ring
Reinstall the blowdown cap onto the AOST. Install the PTFE scavenge and pressure control tubes (see page 51) and the
air outlet hose onto the blowdown cap.
Remove the Oil fill cap (Figure 33).
Oil fill cap

Figure 33 — Oil fill
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Oil sight glass
63

Using a funnel, pour oil into the fill fitting until the oil level in the sight glass
reaches the “MAX” arrow. The air compressor system holds approximately 1 USG (4 L) of oil.
A 45° #12 JIC to ORB fitting can be used to extend the fill port and ease oil filling.
Check the oil level at the sight glass on the front of the AOST. Continue adding
oil until the level is correct.
Replace the fill cap and tighten securely. Start the system and check for oil leaks. Allow the system to build to full system pressure (factory setting 150 psi). Shut the system down. Once the system has sat for 5 minutes, check the oil level through the sight
glass and add oil as necessary.
Verify there are no oil leaks.
Clearing Service Reminders
For systems that show a message “HRSxxx500HRSVC” on the control box: · Press and hold the “” button for approximately 5 seconds until
“DIAGNOSTICS” appears on the display.
· Release the “” button. The system will start scrolling through menus.
When the “SERVICE LOG” is displayed:
· Press and hold the “” button.
Once the system shows “500HR CLEAR?”:
· Push and hold the “” button for approximately 5 seconds until “CLEAR OK”
appears in the display.
The Display Box will show a reminder to “CHECK AIR FILTER” every 100 hours of operation. This is a time based message that will automatically disappear after 6 hours of operation.

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Diagnostics and Troubleshooting
Read the “Maintenance and Repair Safety” section prior to performing any work on the system (beginning on page 52). Wear appropriate Personal Protective Equipment and follow all industry standard safety practices.
For the following tests, isolate the AOST from all downstream (customer supplied) equipment.
If the Hydraulic Driven Air Compressor system is still within the warranty period, see the warranty claim process on page 9 prior to commencing with any diagnostics or repairs.
Problem diagnosis should follow sound, recognized practices. Quick and accurate diagnosis of problems will involve the following:
· Follow industry standard safety practices. · Accurately identify the problem by operating the system (provided it is safe to
do so).
· Determining the possible causes for the problem by understanding how the
system operates.
· Isolating the potential causes by accurate testing using the correct and
recognized procedures.
· Performing proper repairs using the correct procedures and the recommended
replacement parts.
· Performing proper post repair testing to ensure that the repairs were effective. · Electrical testing should be performed according to the processes described
in the troubleshooting charts and in conjunction with any documentation provided by VMAC.
· Additional troubleshooting and specific test procedures can be found on
VMAC’s Knowledge Base www.kb.vamacair.com.
See “System Adjustments (Diagnostics Mode)” on page 47 for instruction to access diagnostic information.

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Key Temperatures
Hydraulic Fluid too cold: -13 °F (-25 °C) and below The hydraulic fluid is too cold and must be warmed prior to starting the system.
Cooler fan enable The cooler fan will automatically turn on under the following conditions (The control system prioritizes compressor oil temperature above the hydraulic fluid temperature):
· The compressor oil temperature reaches 190 °F (88 °C). · The hydraulic fluid temperature reaches 151 °F (66 °C) and the compressor
oil temperature is above 171 °F (77 °C).
Cooler fan enable Cooler fan turns off The cooler fan will automatically turn off under the following conditions (The control system prioritizes compressor oil temperature above the hydraulic fluid temperature):
· The compressor oil temperature drops to 162 °F (72 °C) (or below). · The hydraulic fluid temperature reaches 122 °F (50 °C) and the compressor
oil temperature is below 171 °F (77 °C).
Cold Start The system will remain in “Soft Start” while the hydraulic fluid and compressor oil temperature are within the following parameters:
· Hydraulic fluid temperature below: 41 °F (5 °C). · Compressor oil temperature below: 113 °F (45 °C).
See page 42 for detailed information on cold start and warming modes.
Over temperature shut down The system will automatically shut down if either of the following conditions occur:
· The hydraulic fluid reaches 190 °F (88 °C). · The compressor oil reaches 280 °F (138 °C).

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Diagnostic Mode Error Codes

Error Code

Display

01 OVER TEMP COMP

02 OVER TEMP HYD

04

COMP PROBE SHORT

Fault

Possible Problem(s)

Compressor oil is above Compressor temperature is above 280 °F (138 °C) and the system is shutting down.
Hydraulic fluid is above 188 °F (87 °C) and the system is shutting down.

· Low compressor oil level.
· Faulty or crushed cooler hoses.
· Cooling fan not operating.
· Insufficient air-flow or ventilation.
· Failed temperature probe or faulty electrical connection.
· Incorrect compressor oil used. See “Compressor is getting too hot and is shutting down.” on page 72.
· Insufficient air-flow or ventilation.
· Fan not operating.
· Failed temperature probe or faulty electrical connection.
· Insufficient hydraulic reservoir size.
· Incorrect hydraulic hose size.
· Too many restrictions in hydraulic circuit.
See “Hydraulic fluid is too hot and the system is shutting down.” on page 72.

Compressor temperature probe wires shorted or failed.

Repair wiring to probe.

Hydraulic temperature 05 HYD PROBE SHORT probe wires shorted or
failed.

Repair wiring to probe.

07

Compressor temperature COMP PROBE OPEN probe disconnected or
failed.

· Test temperature probe. · Repair wiring to probe.

08 HYD PROBE OPEN

Hydraulic temperature probe disconnected or failed.

· Test temperature probe. · Repair wiring to probe.

11

PRESSURE SENSOR?

Failed pressure sensor or bad electrical connection.

Check pressure sensor and wiring connections.

Faulty electrical connections. 12 CONNECTION ERR Failed Control Box or Display Box.

Check electrical connections. Bypass extension harness to test. Check Control and Display boxes for damage.

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Display Box Messages

Warning/Information Warning/Information

Message

Description

Corrective Action

HYD OIL TOO COLD

The hydraulic fluid temperature is below -13 °F (-25 °C).

Hydraulic fluid must be heated prior to the system starting.

HYD OIL WARMING, HYD xxxF/xxxC

The hydraulic fluid is between -13 °F (-25 °C) and 5 °F (-15 °C).

· Compressor will not engage until the hydraulic fluid has warmed to 5 °F (-15 °C).
· Continue circulating hydraulic fluid until system warms sufficiently.
If installed, VMAC Cold Climate Kit (P/N: A700280) will enable automatically to speed hydraulic fluid warm up.

SOFT START xxxPSI

The system has started but the compressor oil is too cool for maximum output.

System is in unloaded state until both the compressor oil and hydraulic fluid have reached normal operating temperature (page 42).

STANDBY xxxPSI

The air pressure remained higher than the restart pressure for the duration of the standby delay time.

Hydraulic solenoid is deenergized. System monitors air pressure and compressor oil / hydraulic fluid temperatures. If air pressure drops below restart pressure, or compressor oil drops below 90 °F (32 °C), or hydraulic fluid drops below 5 °F (-15 °C), the system will restart and run until the system is within the standby parameters again.

CHECK AIR FILTER

The system reminds the operator to check the condition of the air filter every 100 hours.

Check air filter and replace as needed. Message will automatically disappear after 6 hrs of operation.

HRS:XXXX:XX 500S

The system reminds the operator to service the system every 500 hours.

· Perform 500 hour service on system (P/N: A700156).
· Once complete, enter Diagnostics Mode and clear the service reminder (see page 47).

BATTERY LOW

Voltage supplied to system is too low.

See “System runs then shuts down, and display goes blank, then scrolls company information.” on page 70.

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Symptoms

Symptom
Air pressure won’t build past 40 psi (approx.).

Possible Cause
System is in “SOFT START”. Air solenoid failure. Pressure sensor has failed or there is a problem with electrical connections.

Corrective Action
Wait for system to warm up. Check air solenoid and wiring.
Check pressure sensor and wiring.

Symptom
Low air pressure.

Possible Cause

Corrective Action

Air receiver tank drain open. Close air receiver tank drain.

Air leak.

Check air hoses and fittings for damage or wear.

Air demand too high.

· Reduce air consumption.
· Install air receiver tank (see accessories on page 79).

Check for air venting from Blowdown system stuck open. the blowdown cap while the
system is running.

Air solenoid failure.

Check air solenoid and wiring.

Not enough hydraulic flow.

Connect a hydraulic flow meter with pressure gauge.
· Ensure adequate hydraulic flow and pressure for the application and desired cfm (see page 17).
· Ensure engine rpm is being maintained when load is applied.

Hydraulic motor failure.

Perform case drain flow test.

Symptom
Air pressure relief valve opens.

Possible Cause

Corrective Action

Compressor system pressure exceeding 200 psi.

· Install pressure gauge at AOST outlet to confirm pressure is above 200 psi.
· Check pressure sensor.

Air pressure relief valve failure (opens below 200 psi).

Replace pressure relief valve.

Unload solenoid has failed energized.

Check solenoid and wiring.

Inlet poppet O-ring dislodged.

Contact VMAC Technical Support.

PTFE Pressure Control tube disconnected or failed.

Check PTFE tube between air solenoid and inlet valve.

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Symptom
No power to display box.

Possible Cause

Corrective Action

· Check display box Blown fuse or bad connection. connections.
· Replace fuse inside unit.

No power from Control Box.

Check for 12 V from Control Box to Display Box.

Symptom
“DIAGNOSTICS” showing on the display box as soon as
system is powered on.

Possible Cause
“” button is stuck on.

Corrective Action
Replace keypad.

Symptom

Possible Cause
Start up conditions not met.

System does not start when activated.

Hydraulic solenoid failure.
Hydraulic motor or compressor seized. Faulty Control Box connections.

Corrective Action
Check display box for messages (see page 41). Check solenoid and connections. Try to rotate compressor and hydraulic motor.
Verify Control Box ground.

Symptom

Possible Cause

System runs then shuts down, and display goes blank, then Issue with supplied power. scrolls company information.

Corrective Action
· Wire gauge from vehicle battery is too small. Install the correct gauge of wire (see page 24).
· Check electrical connections.
· Measure voltage at the input to the Hydraulic Driven Air Compressor when it is running and with the fan on to ensure full voltage.
· Check charging system.

Symptom
Water in the air stream.

Possible Cause

Corrective Action

No Filter/Regulator/Lubricator (FRL) installed.

Install FRL.

FRL failure (if installed).

Check drain on filter.

Air receiver tank not drained regularly (if installed).

Drain air receiver tank daily.

Excessive water in compressor oil.

Perform 500 hour service (P/N: A700156). See “Excessive water in compressor oil.” on page 71 to troubleshoot.

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Symptom
Excessive water in compressor oil.

Possible Cause
Very short duty cycle.
Cooling fan always running.

Corrective Action
· Install air receiver tank. · Perform 500 hour service
(P/N: A700156).
· Perform 500 hour service (P/N: A700156).
· See “Key Temperatures” on page 66.
If the system is running within the parameters, contact VMAC technical support.

Symptom

Possible Cause
Compressor was shut down while building air.

Unit operating on grade greater than 15°.

Excessive oil in the air stream Lack of service. (oil carry over). AOST overfilled. Failed coalescing filter. Clogged scavenge screen. Poor fit between coalescing filter and AOST/poor seal at O-rings.

Corrective Action
Stop air demand and allow system to build to full system pressure (150 psi) prior to turning the compressor off. Level the vehicle and run the system. Oil carry over may take up to 45 minutes to dissipate. Service unit every 500 hours or annually, whichever occurs first. Correct the oil level. Replace coalescing filter. Clean scavenge screen (see page 60).
Replace parts as necessary.

Symptom
Oil out the air filter / air filter saturated with oil.

Possible Cause
Not enough hydraulic flow.
Using a variable displacement hydraulic pump. Hydraulic motor failure.

Corrective Action
Connect a hydraulic flow meter with pressure gauge.
· Ensure adequate hydraulic flow and pressure for the application and desired cfm (see page 17).
· Ensure engine rpm is being maintained when load is applied.
· “Pressure Compensated” variable displacement, pump: Install VMAC Closed Center Manifold (see page 81).
· “Load Sensing” variable displacement pump: Contact VMAC Technical Support.
Perform case drain flow test.

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Symptom

Possible Cause

Insufficient air-flow or ventilation.

Hydraulic fluid is too hot and the system is shutting down.
Hydraulic fluid above 188 °F (87 °C).

Fan not operating.
Failed temperature probe or bad electrical connection.
· Insufficient hydraulic reservoir size.
· Incorrect hydraulic hose size.
· Too many restrictions in hydraulic circuit.

Corrective Action
· Ensure cooler is not blocked.
· Open cabinet door (if installed in an enclosure).
· Improve ventilation. · Move Hydraulic Driven Air
Compressor out of cabinet. · Check fan and relay. · Check connections. Check temperature probe and wiring connections.
Have hydraulic circuit inspected/tested by qualified hydraulic specialist.

Symptom

Possible Cause

Corrective Action

Low compressor oil.

Add oil as necessary (see page 54). See “Excessive oil in the air stream (oil carry over) ” on page 71 to troubleshoot.

Compressor oil flow restricted.

Compressor is getting too hot and is shutting down.
Compressor temperature is above 280 °F (138 °C).

Cooling fan not operating.

Insufficient air-flow or ventilation.

· Check oil filter for blockage.
· Remove hoses and check for blockage.
· Check cooler for blockage.
· Check fan and relay. · Check connections.
· Ensure cooler and air filter are not blocked.
· Open cabinet door (if installed in an enclosure).
· Improve ventilation. · Move Hydraulic Driven Air
Compressor out of cabinet.

Failed temperature probe or bad electrical connection.

Check temperature probe and wiring connections.

Incorrect compressor oil used. Incorrect compressor oil used.

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Hydraulic Testing
Ensure the hydraulic oil has cooled and that the and air and hydraulic systems are depressurized prior to performing any testing or servicing on the system.
Ensure all hoses, fittings and gauges used during testing are rated for the operating pressure of the system being tested.
These instructions are provided as a general guideline only and are not considered to be comprehensive. VMAC is unable to provide hydraulic circuit designs or consult on specific hydraulic installations. If the system does not meet VMAC’s requirements, we recommend consultation with a hydraulic specialist.
A hydraulic flow meter with pressure gauge is necessary to verify that the hydraulic circuit powering the VMAC Hydraulic Driven Air Compressor is within specification (Figure 34).
High pressure gauge

Flow Meter

Flow valve

Return port

High pressure port

Direction of flow

Figure 34 — Hydraulic test tool

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Compressor Test
Connect the hydraulic test tool in-line into the “PRESSURE IN” side of the
hydraulic manifold (Figure 35).
Hydraulic manifold

Figure 35 — Install hydraulic test tool
With the hydraulic test tool valve opened completely, activate the hydraulic
system.
Observe the flow meter and ensure the flow is between 9 gpm ­ 14 gpm. With the compressor off, increase the pressure to 2,800 psi with the test tool
(this simulates the load created by the VMAC Hydraulic Driven Air Compressor).
If the system will not reach 2,800 psi, the hydraulic circuit is not meeting the minimum requirements to run the VMAC Hydraulic Driven Air Compressor.
VMAC suggests working with a local hydraulic expert to diagnose any issues or adjust the hydraulic circuit.
Open the hydraulic test tool valve completely. Activate the compressor. Observe the flow meter and ensure the hydraulic flow remains within the
specifications listed above.
Observe the pressure gauge and ensure the pressure is below 2,600 psi.

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Hydraulic Pump Test (Bypassing the VMAC System)
The following test ensures the VMAC Hydraulic Driven Air Compressor is receiving the required hydraulic pressure and flow.
Remove the line connected to the “PRESSURE IN” port of the VMAC Hydraulic
Driven Air Compressor and connect it to high pressure port of the hydraulic test tool (Figure 36).
Plug manifold ports

“RETURN OUT” line

“PRESSURE IN” line

Figure 36 — Install hydraulic test tool
Remove the line connected to the “RETURN OUT” port of the VMAC Hydraulic
Driven Air Compressor and connect it to return port of the hydraulic test tool (Figure 36).
Plug ports on the VMAC hydraulic manifold to prevent contaminants from
entering the system (Figure 36).
With the hydraulic test tool valve opened completely, activate the hydraulic
system.
Observe the flow meter and ensure the flow is between 9 gpm ­ 14 gpm.

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Using the valve on the hydraulic test tool, increase the pressure to 2,800 psi
(this simulates the load created by the VMAC Hydraulic Driven Air Compressor.
If the system will not reach 2,800 psi, the hydraulic circuit is not meeting the minimum requirements to run the VMAC Hydraulic Driven Air Compressor.
VMAC suggests working with a local hydraulic expert to diagnose any issues or adjust the hydraulic circuit.
Observe the flow meter and ensure the hydraulic flow is between 9 gpm ­ 14
gpm.

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Air Receiver Tank
Pressure in the air receiver tank will not be relieved when the compressor system blows down. This is normal operation. Prior to performing any service work on the system, discharge any stored air in the air receiver tank.
The system has a built-in check valve. Use of an additional check valve is not required and may cause erratic performance.
If an air receiver tank will be used with this system, the following installation procedure must be used to prevent damage to the system.
The VMAC compressor system will automatically depressurize when shutdown. The AOST has a built in check valve that prevents blow back and moisture from the receiver tank entering the AOST. Installation of an additional check valve will cause erratic performance. While the air receiver tank can be installed at any height in relation to the AOST, the discharge hose running from the AOST must be installed as high as possible on the air receiver tank to prevent problems with condensation that may have accumulated in the receiver tank (Figure 37). Drain the condensed water from the receiver tank daily.
Install the line to the receiver tank as high as possible

AOST

Air Receiver Tank
Figure 37 — Air receiver tank

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Recommended Accessories
While the compressor system will function without the following accessories, VMAC strongly recommends their use for optimal performance.
See the “Accessory Product” section of this manual on page 79 for a list of products available for purchase through VMAC.
Receiver Tank
An air receiver tank provides a buffer as it gives the compressor time to react by increasing the engine speed and producing air before the tool stalls. It also has the advantage of lowering the duty cycle of the compressor system.
Pressure Gauge
While not critical to system performance, a pressure gauge is important for fine tuning the system and simplifies any potential troubleshooting. Install a 200 psi pressure gauge downstream of the air discharge valve.
Pressure Regulator and/or Lubricator or FRL
The compressor can produce air pressures up to approximately 150 psi (1035 kPa). It is the responsibility of the user to know the pressure and air flow requirements of the tools powered by the air compressor system.
An appropriate air pressure regulator and lubricator can be installed downstream of the air discharge valve. Failure to regulate the air pressure may cause damage to the tool.

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Accessory Products from VMAC
Compressor Service Kits
500 Hour or 6 Month / 1 Year Service Kit Part number: A700156 Includes VMAC high performance compressor oil, oil filter, air filter, coalescing filter, pressure relief valve, muffler, and next service due decal.

Air Aftercooler — 70 cfm
Part number: A800070 Improves tool performance and extends the life of air tools; removes up to 80% of water from compressed air; includes automatic water drain.
· Max air flow: 70 cfm / 175 psi. · Port size: 3/4 in NPT inlet and outlet. · Electrical: 12 V. · Dimensions: 17 in (43.2 cm) L × 8.0 in (20.3 cm)
W. × 14.5 in (36.8 cm) H.
· Weight: 35 lb (15.8 kg).
Filter Regulator Lubricator (FRL) — 70 cfm
Part number: A700151 Extends the life of air tools; filter removes contaminants from the compressed air, adjustable regulator can reduce air pressure going to tools, lubricator adds atomized tool oil to the air stream to lubricate air tools (Tool oil not included).
· Max air flow: up to 70 cfm / 150 psi · Port size: 3/4 in NPT inlet and outlet
1/2 in × 50 ft Hose Reel
Part number: A700007 Spring-loaded 1/2 in × 50 ft hose reel; steel construction; full flow shaft and swivel for maximum performance.

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6 Gallon Air Receiver Wing Tank
Part number: A300056 Air receiver tanks are used for lowering compressor duty cycle and removing water from compressed air; recommended for optimum operation of all VMAC Gas Driven, Diesel Driven, Hydraulic, and UNDERHOOD40 air compressors. Manufactured to FMVSS 121 standard; includes fittings, 170 psi pressure relief valve, and tank drain.
· Max pressure: up to 170 psi. · Dimensions: 32 in (81.3 cm) L × 8 in (20.3 cm) D. · Weight: 23 lb (10.4 kg).
10 Gallon Air Receiver Tank w/ Mounting Feet
Part number: A300047 Air receiver tanks are used for lowering compressor duty cycle and removing water from compressed air. Recommended for optimum operation of VMAC Hydraulic Air Compressors, VMAC Diesel Driven Air Compressors, UNDERHOOD40, UNDERHOOD70 ­ Green Series Air Compressors, and VMAC Multifunction Power Systems, which include standby mode; ASME certified; includes fittings, 200 psi pressure relief valve, tank drain, and 200 psi pressure gauge.
· Max pressure: up to 200 psi. · Dimensions: 30 in (76.2 cm) L × 10 in (25.4 cm) D. · Weight: 33 lb (15 kg).
35 Gallon Air Receiver Wing Tank
Part number: A300010 Air receiver tanks are used for lowering compressor duty cycle and removing water from compressed air. Recommended for optimum operation of VMAC Diesel Air Compressors, Hydraulic Air Compressors, UNDERHOOD40, UNDERHOOD70 ­ Green Series Air Compressors, and VMAC Multifunction Power Systems, which include standby mode; ASME certified; includes fittings, 200 psi pressure relief value, tank drain, and 200 psi pressure gauge.
· Max pressure: up to 200 psi. · Dimensions: 73 3/4 in (187.3 cm) L × 14 in (35.6 cm) D. · Weight: 95 lb (43.1 kg).

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Hydraulic Oil Cooler
Part number: A850001 Recommended for high duty cycle industrial and work truck hydraulic systems working in hot climates (100 °F (37 °C) and above); capable of removing up to 33,750 BTU / Hr.
· Hydraulic flow: 5 – 20 GPM (19 – 76 LPM) · Pressure rating: Up to 500 psi (345 kPa) · Electrical: 12 V @ 10 Amps · Dimensions: 17.0 in (43.2 cm) L × 8.0 in (20.3 cm)
W x 13.0 in (33 cm) H
· Weight: 30 lbs (13.5 kg)
Closed Center Manifold
H40 (40 cfm): A700190 Allows VMAC’s Hydraulic driven air compressor systems to be used with pressure compensated variable displacement (closed center) hydraulic systems.
Note: The VMAC Closed Center Manifold is not compatible with “load sensing” variable displacement hydraulic systems.
Cold Climate Kit
Part number: A700280 Fully automated manifold heater block; recommended for extreme cold climates; when hydraulic oil temperatures fall below 5°F (-15°C), a solenoid will energize and heat the hydraulic oil.

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Error and Service Logs
This form can also be found on the VMAC Knowledge Base by scanning (or clicking) the QR code below.

Name: Phone#: VMAC Service Ticket/ CSR (If issued):

Company: Email: Preferred VMAC Dealer (Optional):

See “Entering DIAGNOSTICS mode” on page 47 for instruction on how to retrieve the service logs and error messages. The error code legend can be found on page 67. Once the form is filled out it can be emailed to tech@vmacair.com or faxed to 877-740-3203.

HOURS

ERRORS E E E E E E E E E E

01 02 03 04 05 06 07 08 09 0 10

Service S 0 1 S02

S03 S04 S05 S06 S07 S08 S09 S 0 10

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Notes

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Warranty Registration

This form must be fully completed and returned to VMAC at the time the vehicle is put into service. Warranty may be void if this form is not received by VMAC within 3 months of receiving the vehicle, or 200 hours of operation, whichever occurs first.
VMAC’s Warranty policy and registration can be viewed online at: www.vmacair.com/warranty

Product Information

System Identification Number: H 0 0 0 0

Owner / End User Information

Company Name:

City:

State / Province:

Phone: ( ) ­

Email Address:

Date vehicle was put into service:

/ /

Day

Month Year

Installer Information
Installer Company Name: City:

State / Province:

Submitted by
Name: Email:

Phone: ( )

­

Vehicle Information (Optional)

Unit:

Year:

Make:

Model:

Vehicle Identification Number:

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Manufactured by

®

888-241-2289

tech@vmacair.com

877-740-3202

warranty@vmacair.com

www.vmacair.com

kb.vmacair.com

1333 Kipp Road, Nanaimo, B.C., V9X 1R3 Canada

References

• VMAC Knowledge Base
• Find A Dealer - VMAC
• Find A Dealer - VMAC
• VMAC Support & Service Resources

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