VENTS VPVO Axial Pressurization Fan User Manual
- June 15, 2024
- VENTS
Table of Contents
- Introduction
- SAFETY REQUIREMENTS
- PURPOSE
- DELIVERY SET
- DESIGNATION KEY
- TECHNICAL DATA
- UNIT DESIGN AND OPERATING PRINCIPLE
- MOUNTING AND SET-UP
- CONNECTION TO POWER MAINS
- COMMISSIONING
- TECHNICAL MAINTENANCE
- STORAGE AND TRANSPORTATION REGULATIONS
- MANUFACTURER’S WARRANTY
- Customer Support
- References
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)
VENTS VPVO Axial Pressurization Fan
Introduction
This user’s manual is a main operating document intended for technical,
maintenance, and operating staff.
The manual contains information about purpose, technical details, operating
principle, design, and installation of the VPVO unit and all its
modifications.
Technical and maintenance staff must have theoretical and practical training
in the field of ventilation systems and should be able to work in accordance
with workplace safety rules as well as construction norms and standards
applicable in the territory of the country.
SAFETY REQUIREMENTS
All operations described in this manual must be performed by qualified
personnel only, properly trained and qualified to install, make electrical
connections and maintain ventilation units.
Do not attempt to install the product, connect it to the mains, or perform
maintenance yourself.
This is unsafe and impossible without special knowledge.
Disconnect the power supply prior to any operations with the unit.
All user’s manual requirements as well as the provisions of all the applicable
local and national construction, electrical, and technical norms and standards
must be observed when installing and operating the unit.
Disconnect the unit from the power supply prior to any connection, servicing,
maintenance, and repair operations.
Connection of the unit to power mains is allowed by a qualified electrician
with a work permit for the electric units up to 1000 V after careful reading
of the present user’s manual.
Check the unit for any visible damage of the impeller, the casing, and the
grille before starting installation. The casing internals must be free of any
foreign objects that can damage the impeller blades.
While mounting the unit, avoid compression of the casing! Deformation of the
casing may result in motor jam and excessive noise.
Misuse of the unit and any unauthorised modifications are not allowed.
Do not expose the unit to adverse atmospheric agents (rain, sun, etc.).
Transported air must not contain any dust or other solid impurities, sticky
substances, or fibrous materials.
Do not use the unit in a hazardous or explosive environment containing
spirits, gasoline, insecticides, etc.
Do not close or block the intake or extract vents in order to ensure the
efficient air flow.
Do not sit on the unit and do not put objects on it.
The information in this user’s manual was correct at the time of the
document’s preparation.
The Company reserves the right to modify the technical characteristics,
design, or configuration of its products at any time in order to incorporate
the latest technological developments.
Never touch the unit with wet or damp hands.
Never touch the unit when barefoot.
BEFORE INSTALLING ADDITIONAL EXTERNAL DEVICES, READ THE RELEVANT USER MANUALS.
THE PRODUCT MUST BE DISPOSED SEPARATELY AT THE END OF ITS SERVICE LIFE.
DO NOT DISPOSE THE UNIT AS UNSORTED DOMESTIC WASTE.
PURPOSE
The axial pressurisation fan of VPVO series is used for ventilation of
industrial, administrative, residential and other buildings. It is also used
for pressurisation of fire-fighting equipment and fresh air supply in case of
fire.
The fan is intended for general ventilation in systems with high air flow
rates.
THE UNIT SHOULD NOT BE OPERATED BY CHILDREN OR PERSONS WITH REDUCED PHYSICAL,
MENTAL, OR SENSORY CAPACITIES, OR THOSE WITHOUT THE APPROPRIATE TRAINING.
THE UNIT MUST BE INSTALLED AND CONNECTED ONLY BY PROPERLY QUALIFIED PERSONNEL
AFTER THE APPROPRIATE BRIEFING.
THE CHOICE OF UNIT INSTALLATION LOCATION MUST PREVENT UNAUTHORISED ACCESS BY
UNATTENDED CHILDREN.
DELIVERY SET
Name | Number |
---|---|
Fan | 1 pc. |
User’s manual | 1 pc. |
Packing | 1 pc. |
DESIGNATION KEY
TECHNICAL DATA
- Transported air temperature depends on the applied climatic category (see the designation key).
- The maximum permissible concentration of solids and dust in the handled air is 10 mg/m3.
- The unit is rated as a Class I electrical appliance.
- The units meet the requirements of IPX4 hazardous parts access and water ingress protection standard.
The unit design is constantly being improved, so some models may be slightly different from those ones described in this manual.
-
Casing modification without terminal box.
-
Casing modification with a terminal box.
MODEL | DIMENSIONS [MM] |
---|---|
L | D |
VPVO-400 | 350, 450 |
VPVO-450 | 350, 450, 550 |
VPVO-500 | 350, 450, 550 |
VPVO-560 | 350, 450, 550, 650 |
VPVO-630 | 350, 450, 550, 650, 750 |
VPVO-710 | 450, 550, 650, 750, 850 |
VPVO-800 | 450, 550 |
VPVO-900 | 450, 550, 650, 750 |
VPVO-1000 | 550, 650, 800, 900 |
VPVO-1120 | 550, 650, 800, 900 |
VPVO-1250 | 550, 650, 800, 900 |
UNIT DESIGN AND OPERATING PRINCIPLE
-
Fan with a casing modification without terminal box.
-
Fan with a casing modification with a terminal box.
-
Not included in the delivery set, available as a special accessory.
The all-welded metal casing with rolled flanges results in outstanding
rigidity and minimum clearances between the casing and the blades. There is an
access door in the casing for easy maintenance. All the casing components are
powder coated for improved protection against the environmental effects.
The fan impeller has a split design and is connected to the motors.
The fan is driven by a three-phase asynchronous single-speed motor with a
square-cage rotor installed inside the casing.
The fan casing modifications depend on the electrical cable connection options:
- The cable is connected to the electric motor terminal box via a cable gland in the casing for the modification without a terminal box.
- The cable is connected to the terminal box on the casing for the modification with a terminal box.
MOUNTING AND SET-UP
ALL OPERATIONS DESCRIBED IN THIS USER’S MANUAL MUST BE PERFORMED BY QUALIFIED
PERSONNEL ONLY, PROPERLY TRAINED AND QUALIFIED TO INSTALL AND MAINTAIN
VENTILATION EQUIPMENT.
DO NOT ATTEMPT TO INSTALL THE PRODUCT YOURSELF.
IT IS UNSAFE AND IMPOSSIBLE WITHOUT SPECIAL KNOWLEDGE.
WHILE INSTALLING THE UNIT ENSURE CONVENIENT ACCESS FOR SUBSEQUENT MAINTENANCE AND REPAIR.
Before installing the unit, carry out the following checks:
- Make sure that the fan impeller rotates freely.
- Make sure there is no condensate on the motor.
- Check the electrical resistance of insulation between the motor windings and between each winding and the motor casing.
The fan can be mounted in any position – vertically, horizontally or tilted at
any angle.
FAN INSTALLATION RECOMMENDATIONS
Fan mounting in the ductworks
To ensure smooth airflow at the fan inlet it is recommended to install a
straight air duct segment with a cross section equal to the fan cross section.
The air duct segment must be 3 ÷ 4 D (D is the inner fan diameter). The length
of the straight duct section downstream of the fan must be 1.5 ÷ 2 D.
Installation of shorter air ducts may result in insufficient air pressure and
air flow. The flexible joints VVGF-VO are recommended for vibration damping
and noise attenuation.
Changing diameter installation
When changing from a smaller diameter to a larger one use a connector diffuser
with the maximum opening angle of 12°.
Mounting in case of no ductwork upstream of the fan
If the ductwork is not available at the fan inlet, the inlet cone VK-VO must be installed to improve aerodynamic parameters of the air flow.
Obstructed space installation
To ensure normal operation of the fan in an obstructed space make sure to
provide for a sufficient distance between the inlet and outlet flanges and the
floor, walls, bulky equipment and obstacles.
Installation near bends
To install the fan directly downstream of a bend (elbow) use a curved section
with a large bending radius or an array of internal guide vanes.
- When installing the fan in an air duct, connection to the air ducts is made by means of flanges.
- The O-VO carriers are used for mounting the fans to the floor, walls or ceiling. The carriers are fixed to the ceiling by means of the threaded expansion anchors and mounting studs. Fix threaded expansion anchors to attach the carriers to the floor or to the wall.
- The carriers and the fasteners are not included in the delivery set and are available as specially ordered accessories. Selection of the fasteners must be based on material of a mounting surface and the fan weight. For details, please refer to the Technical data. The fastener selection must be performed by a qualified technician.
After installing the unit, you need to make sure that the fan impeller rotates freely.
CONNECTION TO POWER MAINS
DISCONNECT THE POWER SUPPLY PRIOR TO ANY OPERATIONS WITH THE UNIT.
CONNECTION OF THE UNIT TO POWER MAINS IS ALLOWED BY A QUALIFIED ELECTRICIAN
WITH A WORK PERMIT FOR THE ELECTRIC UNITS UP TO 1000 V AFTER CAREFUL READING
OF THE PRESENT USER’S MANUAL.
THE RATED ELECTRICAL PARAMETERS OF THE UNIT ARE GIVEN ON THE MANUFACTURER’S
LABEL.
ANY TAMPERING WITH THE INTERNAL CONNECTIONS IS PROHIBITED AND WILL VOID THE WARRANTY.
-
The air pressurisation fan is not rated for standalone operation.
-
The fan must be integrated into a ventilation or smoke extraction system with an automatic control system.
-
The fan motor is rated for connection to 400 V/50 (60) Hz three-phase alternating current.
-
Connect the fan motor via the terminal block according to the electrical mains wiring diagram using a durable insulated cable.
-
The terminal block with the terminal markings is housed inside the terminal box.
-
The fans with a casing without a terminal box have the terminal box on the motor.
-
The fans with a casing with a terminal box have the terminal box on the motor.
MAKE SURE THAT THE FAN IMPELLER ROTATES IN THE DIRECTION MARKED BY THE ARROW
ON THE FAN CASING.
IF NECESSARY, CHANGE THE IMPELLER ROTATION DIRECTION BY ALTERING THE PHASE
SEQUENCE ON THE ELECTRIC MOTOR TERMINALS.
ASYNCHRONOUS ELECTRIC MOTOR STARTING METHODS
There are several methods for starting asynchronous squirrel-cage electric
motors.
The most common methods are: direct-on-line (DOL), with a soft starter (SS) or
with a frequency converter (FC).
Direct-on-line starting
In case of direct-on-line starting (i.e. by connecting the motor to the
electric mains with a simple line contactor), the motor starting time
significantly increases due to high inertia of the impeller, which, in turn,
results in high in-rush starting currents in the circuit. These currents of
long duration may cause voltage slumps (especially if the feed line section
falls short of the requirements), which may affect load operation.
The in-rush current consumed by an electric motor in case of DOL starting is
5-8 times larger than the rated value (or even 10-14 times larger in some rare
instances). It should be noted that the torque developed by the motor also
significantly exceeds the rated value.
Upon energisation the motor operates as a transformer with a squirrel-cage
secondary winding formed by the rotor cage with a very low resistance.
The rotor develops high induced current causing a rush of current in the feed
line.
The startup torque during starting averages 0.5-1.5 of the rated torque value.
Despite such advantages as simple construction, high startup current, quick start and low cost, direct-on-line systems are suitable only in the following cases:
- The motor power is low compared to the mains power which limits the adverse effect of the rush of current
- The driven mechanism does not require gradual speed build-up or is equipped with a damping device to smooth out the inrush
- The high startup torque has no adverse effects on the operation of the driven mechanism
Soft start. SS starting
A soft starter gradually increases the voltage supplied to the motor – from
the initial to the rated value.
This starting system can be used to meet the following goals:
- Limit the motor current
- Regulate the torque
Regulation by limiting the current sets the maximum inrush current equal to
300-400 % (or 250 % in some rare instances) of the rated current and reduces
torque characteristics. This type of regulation is especially suited for
turbomachinery such as centrifugal pumps and fans.
Regulation by variation of torque optimizes the torque during startup and
reduces in-rush current in the circuit. These conditions are suitable for
mechanisms with constant load resistance.
This type of soft starting may differ in the implementation pattern:
- Motor start
- Motor start and stop
- Device bridging at the end of start sequence
- Start and stop of several motors in stage circuits
Soft start. FC starting
During the starting the FC raises the frequency from 0 Hz to the electrical
mains frequency (50 or 60 Hz). As the frequency is increased gradually, the
motor can be assumed to operate at its rated speed for a given frequency
value. Furthermore, on the assumption that the motor runs at its rated speed
the nominal torque should be immediately available whereas the current will be
approximately equal to the rated value.
This starting system is used for speed control and regulation and can be used
in the following cases:
- Start with high-inertia load
- Start with high load and limited-capacity power supply source
- Optimization of electric power consumption depending on turbomachinery speed
The aforementioned starting system can be used for all types of mechanisms.
Problems associated with DOL starting
The problems caused by DOL starting may be divided into two groups:
- An abrupt start causes mechanical shock, jolts in the mechanism, shock removal of free play etc.
- A heavy start cannot be completed.
Let us review three variations of a heavy start:
-
The feed line performance is barely sufficient or insufficient to maintain the induced current.
Typical symptoms: Upon starting the circuit breakers at the system input are tripped; the lights, certain relays and contactors go off, and the supply generator shuts down.
Solution: In the best-case scenario an SS device may help reduce the in-rush current to 250 % of the motor rated current. If this is insufficient, an FC is necessary. -
The motor cannot start the mechanism with DOL starting.
Typical symptoms: The motor fails to turn or “freezes” at certain speed which is maintained until actuation of the protection suite. Solution: This problem may not be solved with an SS device. The motor develops insufficient shaft torque. However, this problem can be addressed by using an FC, but each case may be different. -
The motor spins up the mechanism with authority, but fails to reach the rated rotation speed.
Typical symptoms: The input automatic circuit breaker is tripped during spin- up. This often happens with heavy weight fans with a considerable rotation speed.
Solution: Such problems may be addressed with an SS device, but not with 100 % certainty. The closer the motor speed to the rated value during the actuation of the protective equipment, the higher the chances of success. The use of an FC in this case helps solve the problem fundamentally.
Standard switching equipment (automatic circuit breakers, contactors and motor starters) is not designed to withstand prolonged overloads normally causing the fan to shut down automatically DOL starting that continues for a long period of time. Using switching equipment with a higher maximum current rating renders the electric motor protection system less sensitive. As a result the switching equipment will not be able to detect motor overload in time due to a high current sensing threshold. Such problems as mentioned above can only be addressed by utilizing a soft starter or a frequency converter to start the fan.
COMMISSIONING
THE ORGANISATION RESPONSIBLE FOR THE COMMISSIONING SHALL BE RESPONSIBLE FOR PROPER MOTOR PHASING AND STARTING PATTERN SELECTION.
DURING STARTING THE IN-RUSH CURRENTS OF THE FAN MAY SEVERAL TIMES EXCEED THE
RATED VALUES.
SEE “ASYNCHRONOUS ELECTRIC MOTOR STARTING METHODS” IN THE “CONNECTION TO POWER
MAINS” SECTION.
- After fan starting make sure that the electric motor rotates properly without undue vibration and abnormal noise.
- Make sure that the fan impeller rotates in the direction marked by the arrow on the fan casing. If necessary, change the rotation direction of the impeller by reversing the phase sequence (for a three-phase motor) or by rewiring according to the wiring diagram located inside the terminal box (for a single-phase motor).
- Make sure that the fan energy consumption complies with the value given on the equipment nameplate and check the motor for overheating.
- The phase current should be checked once the fan reaches the rated operating conditions.
- Do not switch the fan on and off several times without pauses as this may result in damage to the winding or insulation due to overheating.
TECHNICAL MAINTENANCE
DISCONNECT THE UNIT FROM POWER SUPPLY BEFORE ANY MAINTENANCE OPERATIONS!
MAKE SURE THE UNIT IS DISCONNECTED FROM POWER MAINS BEFORE REMOVING THE
PROTECTION.
PRIOR TO COMMENCING ANY TECHNICAL MAINTENANCE PUT UP A PROHIBITORY SIGN ON THE
FAN STARTING PANEL:
“DO NOT SWITCH ON! MEN AT WORK!”
AVOID LIQUID SPILLS ON THE MOTOR! DO NOT USE AGGRESSIVE SOLVENTS AND SHARP OBJECTS FOR CLEANING!
Prior to performing any technical maintenance and repair disconnect the fan from the electric mains and wait until its rotating parts come to a complete stop.
While performing technical maintenance:
- Check the grounding screw terminals and electric connectors for proper tightness and tighten them up if necessary.
- Check the casing fastening screws for tightness and tighten them up if necessary.
- Check the bolt connecting the motor shaft to the hub for proper tightness and tighten it up if necessary.
- Check the fan impeller for contamination and clean it up if necessary. To clean the impeller, remove the side cover.
Technical maintenance must be carried out at least once a year.
TROUBLESHOOTING
Problem | Possible reasons | Elimination |
---|---|---|
The fan will not start. | No power supply. | Check the mains switch. Check the |
electrical connections according to the wiring diagram.
Jammed motor.| Carefully check the fan impeller for possible seizure and
eliminate it, if necessary. If the impeller is in order, replace the electric
motor.
The switching equipment activates upon fan start-up.| Short circuit in the fan
or the electric circuit between the fan and the switching equipment.|
Eliminate the cause of a short circuit.
Excessive current consumption due to an overload in the electric mains.|
Eliminate the cause of excessive current consumption.
Improper fan starting method.| Use a soft starter or frequency converter to
start the motor (see “Asynchronous Electric Motor Starting Methods” in
the “Connection to power mains” section).
Improper switching equipment.| Re-select the switching equipment in accordance
with the current regulations and equipment specifications.
The installed switching equipment is of poor quality or its actual performance
falls short of the rated values stated by the manufacturer.| Re-select the
switching equipment by choosing a unit which successfully passed commutation
and load tests and has a technical compliance certificate. The selection
should be limited to the top five foreign switching equipment manufacturers.
The fan fails to reach the required rotation speed due to serious overheating
of the fan motor.| Fan motor overloaded.| Eliminate the overload.
Improper fan starting method.| Use a soft starter or frequency converter to
start the motor (see “Asynchronous Electric Motor Starting Methods” in
the “Connection to power mains” section).
The fan motor runs at overload capacity with current consumption in excess of
the rated value.| The fan supplies more air than expected upon motor capacity
selection.| Measure network resistance. Throttle down the network (add
aerodynamic resistance to the air duct network).
Wrong motor phasing. The impeller rotates in the opposite direction of the
arrow on the fan casing.| If necessary, change the impeller rotation direction
by changing the phase sequence on the electric motor terminals.
Air ducts clogged.| Clean the air duct or the impeller.
The fan supplies more air than expected.| The resistance values used during
the ventilation network calculations are too conservative.| Check the air
ducts for proper shape and cross section as well as for any dampers present.
The cross section of air ducts increased and their number reduced during the
installation.| Throttle down the network (add aerodynamic resistance to the
air duct network).
Wrong choice of the fan.| Replace the fan with a unit of proper standard size.
The fan supplies less air than expected.| Wrong calculation of the ventilation
network and wrong selection of the fan.| Re-calculate the network parameters
and select a matching fan.
The network resistance exceeds the design calculations.| Rearrange the
ventilation network to decrease its aerodynamic resistance.
Wrong direction of the impeller rotation.| If necessary, change the impeller
rotation direction by changing the phase sequence on the electric motor
terminals (see the “Commissioning” section).
Air leak through a loose air duct connection.| Eliminate the air leak. Seal
the air duct connection.
Impeller or air duct contamination with foreign objects or debris.| Clean the
impeller or the air ducts from foreign objects or debris.
Excessive noise or vibration both inside the fan and in the circuit.| Loose
screw connections.| Check the screw connections for proper tightness.
No flexible joints between the fan and the ventilation network on the suction
and discharge sides.| Install flexible joints.
Loose connection of valves and dampers to the air ducts.| Tighten up the
fasteners of valves and dampers.
Impeller or air duct contamination with foreign objects or debris.| Clean the
impeller or the air ducts from foreign objects or debris.
Worn bearings.| Replace the bearings.
Unstable power supply, unstable motor operation.| Check the stability of power
supply parameters and electric motor operation.
STORAGE AND TRANSPORTATION REGULATIONS
- Store the unit in the manufacturer’s original packaging box in a dry closed ventilated premise with temperature range from +5 °C to + 40 °C and relative humidity up to 70 %.
- Storage environment must not contain aggressive vapors and chemical mixtures provoking corrosion, insulation, and sealing deformation.
- Use suitable hoist machinery for handling and storage operations to prevent possible damage to the unit.
- Follow the handling requirements applicable for the particular type of cargo.
- The unit can be carried in the original packaging by any mode of transport provided proper protection against precipitation and mechanical damage. The unit must be transported only in the working position.
- Avoid sharp blows, scratches, or rough handling during loading and unloading.
- Prior to the initial power-up after transportation at low temperatures, allow the unit to warm up at operating temperature for at least 3-4 hours.
RISK OF UNIT DAMAGE.
ROTATE THE MOTOR ROTOR BY HAND TO A NEW POSITION EVERY 3 MONTHS DURING
STORAGE.
MANUFACTURER’S WARRANTY
The product is in compliance with EU norms and standards on low voltage
guidelines and electromagnetic compatibility. We hereby declare that the
product complies with the provisions of Electromagnetic Council Directive
2014/30/EU, Low Voltage Directive 2014/35/ EU and CE-marking Directive
93/68/EEC. This certificate is issued following test carried out on samples of
the product referred to above.
The manufacturer hereby warrants normal operation of the unit for 24 months
after the retail sale date provided the user’s observance of the
transportation, storage, installation, and operation regulations. Should any
malfunctions occur in the course of the unit operation through the
Manufacturer’s fault during the guaranteed period of operation, the user is
entitled to get all the faults eliminated by the manufacturer by means of
warranty repair at the factory free of charge. The warranty repair includes
work specific to elimination of faults in the unit operation to ensure its
intended use by the user within the guaranteed period of operation. The faults
are eliminated by means of replacement or repair of the unit components or a
specific part of such unit component.
The warranty repair does not include:
- Routine technical maintenance
- Unit installation/dismantling
- Unit setup
To benefit from warranty repair, the user must provide the unit, the user’s manual with the purchase date stamp, and the payment paperwork certifying the purchase. The unit model must comply with the one stated in the user’s manual. Contact the Seller for warranty service.
The manufacturer’s warranty does not apply to the following cases:
- User’s failure to submit the unit with the entire delivery package as stated in the user’s manual including submission with missing component parts previously dismounted by the user.
- Mismatch of the unit model and the brand name with the information stated on the unit packaging and in the user’s manual.
- User’s failure to ensure timely technical maintenance of the unit.
- External damage to the unit casing (excluding external modifications as required for installation) and internal components caused by the user.
- Redesign or engineering changes to the unit.
- Replacement and use of any assemblies, parts and components not approved by the manufacturer.
- Unit misuse.
- Violation of the unit installation regulations by the user.
- Violation of the unit control regulations by the user.
- Unit connection to power mains with a voltage different from the one stated in the user’s manual.
- Unit breakdown due to voltage surges in power mains.
- Discretionary repair of the unit by the user.
- Unit repair by any persons without the manufacturer’s authorization.
- Expiration of the unit warranty period.
- Violation of the unit transportation regulations by the user.
- Violation of the unit storage regulations by the user.
- Wrongful actions against the unit committed by third parties.
- Unit breakdown due to circumstances of insuperable force (fire, flood, earthquake, war, hostilities of any kind, blockades).
- Missing seals if provided by the user’s manual.
- Failure to submit the user’s manual with the unit purchase date stamp.
- Missing payment paperwork certifying the unit purchase.
The manufacturer shall not accept any claims with regards to the condition of the paint-and-lacquer coating (hereinafter PLC) in the following cases:
- Dents, cracks, scratches and abrasions of the PLC sustained during handling, mounting and assembly operations.
- Progress of corrosion on areas damaged with stones, sand, and roof coat tar during the performance of roofing work.
- Signs of direct exposure of the PLC to excessive temperatures, which occurred during the performance of roofing work.
- Violation of regulations on transportation, storage, installation, and operation of the unit.
- Presence of damage caused by exposure to industrial and chemical emissions, acidic or alkaline pollution, sap or other factors not related to normal operating conditions.
FOLLOWING THE REGULATIONS STIPULATED HEREIN WILL ENSURE A LONG AND TROUBLE- FREE OPERATION OF THE UNIT.
USER’S WARRANTY CLAIMS SHALL BE SUBJECT TO REVIEW ONLY UPON PRESENTATION OF THE UNIT, THE PAYMENT DOCUMENT AND THE USER’S MANUAL WITH THE PURCHASE DATE STAMP.
Customer Support
http://www.ventilation-system.com/
References
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