COPELAND AE24-1105 R6 Principles Of Cleaning Refrigeration Systems Instructions
- June 1, 2024
- Copeland
Table of Contents
COPELAND AE24-1105 R6 Principles Of Cleaning Refrigeration Systems
Product Information
Specifications:
- Model: AE24-1105 R6
- Date: Nov 2023
- Contains polyol ester (POE) oils
Product Usage Instructions
Safety Information:
It is crucial to follow all safety precautions and guidelines provided in the
manual to prevent potential hazards and ensure safe operation of the
compressor system.
Responsibilities, Qualifications, and Training:
All individuals involved in the design, installation, purchase,and servicing
of the system should be aware of the hazards and precautions outlined in the
manual. Proper training and qualifications are essential.
Terminal Venting and Pressurized System Hazards:
Be cautious of terminal venting which can result in pressurized oil,
refrigerant, and debris being ejected from the compressor. Visit this
link for more details on terminal venting.
Flammable Refrigerant Hazards:
Release of flammable refrigerant can pose fire and explosion risks. Systems
using flammable refrigerants are designed to reduce ignition risks, but
precautions should still be taken.
For additional information, refer to this link.
Electrical Hazards:
Always de-energize the system and discharge capacitors before servicing to
avoid electric shock hazards.
Lifting Hazards:
Exercise caution when moving heavy system components to prevent personal
injury. Utilize proper lifting techniques at all times.
POE Oil Hazards:
Avoid contact between POE oils and certain polymers as it may cause damage.
Ensure that non-essential personnel stay clear of the compressor during
service.
Hot Surface and Fire Hazards:
Wait for the compressor to cool down before touching to prevent burns. Take
precautions when brazing system components to avoid igniting nearby materials.
Frequently Asked Questions (FAQ):
Q: How should I handle a compressor’s electrical terminal pin losing its
seal?
A: If a compressor’s electrical terminal pin loses its seal,ensure that
the system is de-energized before addressing the issue. Follow proper safety
protocols to avoid any potential hazards.
Q: What should I do if I suspect a refrigerant leak?
A: If you suspect a refrigerant leak, immediately ventilate the area,
evacuate personnel, and contact a qualified technician to assess and repair
the leak to prevent any safety risks.
IMPORTANT SAFETY INFORMATION
Those involved in the design, manufacture, and installation of a system, system purchasers, and service personnel may need to be aware of hazards and precautions discussed in this section and throughout this document. OEMs integrating the compressor into a system should ensure that their own employees follow this bulletin and provide any necessary safety information to those involved in manufacturing, installing, purchasing, and servicing the system.
Responsibilities, Qualifications and Training
- OEMs are responsible for system design, selection of appropriate components, integration of this component into the system, and testing the system. OEMs must ensure that staff involved in these activities are competent and qualified.
- OEMs are also responsible for ensuring that all product, service, and cautionary labels remain visible or are appropriately added in a conspicuous location on the system to ensure they are clear to any personnel involved in the installation, commissioning, troubleshooting or maintenance of this equipment.
- Only qualified and authorized HVAC or refrigeration personnel are permitted to install, commission, troubleshoot and maintain this equipment. Electrical connections must be made by qualified electrical personnel.
- Observe all applicable standards and codes for installing, servicing, and maintaining electrical and refrigeration equipment.
Terminal Venting and Other Pressurized System Hazards
If a compressor’s electrical terminal pin loses its seal, pressurized oil,
refrigerant, and debris may spray out. This is called “terminal venting”.
The ejected debris, oil, and refrigerant can injure people or damage property.
The oil and refrigerant spray can be ignited by electrical arcing at the
terminal or any nearby ignition source, producing flames that may project a
significant distance from the compressor. The distance depends on the pressure
and the amount of refrigerant and oil mixture in the system. The flames can
cause serious or fatal burns and ignite nearby materials.
Each compressor has a terminal cover or molded plug that covers electrical
connections. The cover or plug helps to protect against electric shock and the
risks of terminal venting. If terminal venting occurs, the cover or plug helps
contain the spray of refrigerant and oil and reduces the risk of ignition. If
ignition occurs, the plug or cover helps contain the flames. However, neither
the terminal cover nor the molded plug can completely eliminate the risk of
venting, ignition, or electric shock.
See https://www.copeland.com/en-us/training-support/safety-resource-center
/terminal-venting for more details about terminal venting.
Additionally, a compressor’s refrigerant lines keep refrigerant and oil under
pressure. When removing or recharging refrigerant from this component during
service, this can pose a pressurized fluid hazard.
Flammable Refrigerant Hazards
If flammable refrigerant is released from a system, an explosive concentration
can be present in the air near the system. If there is an ignition source
nearby, a release of flammable refrigerant can result in a fire or explosion.
While systems using flammable refrigerant are designed to mitigate the risk of
ignition if the refrigerant is released, fire and explosion can still occur.
See https://www.copeland.com/en-us/training-support/safety-resource-center
/flammable-refrigerants for more information on flammable refrigerant safety.
Electrical Hazards
Until a system is de-energized, and capacitors have been discharged, the
system presents a risk of electric shock.
Hot Surface and Fire Hazards
While the system is energized, and for some time after it is deenergized, the
compressor may be hot. Touching the compressor before it has cooled can result
in severe burns. When brazing system components during service, the flames can
cause severe burns and ignite nearby combustible materials.
Lifting Hazards
Certain system components may be very heavy. Improperly lifting system
components or the compressor can result in serious personal injury. Use proper
lifting techniques when moving.
POE Oil Hazards
This equipment contains polyol ester (POE) oils. Certain polymers (e.g.,
PVC/CPVC and polycarbonate) can be harmed if they come into contact with POE
oils. If POE oil contacts bare skin, it may cause an allergic skin reaction.
Precautions
- Always wear personal protective equipment (gloves, eye protection, etc.).
- Keep a fire extinguisher at the jobsite at all times.
- Keep clear of the compressor when power is applied.
- IMMEDIATELY GET AWAY if you hear unusual sounds in the compressor. They can indicate that terminal pin ejection may be imminent. This may sound like electrical arcing (sizzling, sputtering or popping). However, terminal venting may still occur even if you do not hear any unusual sounds.
- Never reset a breaker or replace a blown fuse without performing appropriate electrical testing
- A tripped breaker or blown fuse may indicate an electrical fault in the compressor. Energizing a compressor with an electrical fault can cause terminal venting. Perform checks to rule out an electrical fault.
- Disconnect power and use lock-out/tag-out procedures before servicing.
- Before removing the terminal cover or molded plug, check that ALL electrical power is disconnected from the unit. Make sure that all power legs are open. (Note: The system may have more than one power supply.)
- Discharge capacitors for a minimum of two minutes
- Always use control of hazardous energy (lock-out/tag-out) procedures to ensure that power is not reconnected while the unit is being serviced.
- Allow time for the compressor to cool before servicing.
- Ensure that materials and wiring do not touch high temperature areas of the compressor.
Keep all non-essential personnel away from the compressor during service.
Remove refrigerant from both the high and low side of the compressor. Use a recovery machine and cylinder designed for flammable refrigerants. Do not use standard recovery machines because they contain sources of ignition such as switches, high- and low-pressure controls, and relays. Only vent the refrigerant into the atmosphere if the system is in a well-ventilated area.
- Never us a torch to remove the compressor. Only tubing cutters should be used.
- Use an appropriate lifting device to install or remove the compressor.
- Never install a system and leave it unattended when it has no charge, a holding charge, or with the service valves closed without electrically locking out the system.
- Always wear appropriate safety glasses and gloves when brazing or unbrazing system components.
- Charge the system with only approved refrigerants and refrigeration oils.
- Keep POE oils away from certain polymers (e.g., PVC/CPVC and polycarbonate) and any other surface or material that might be harmed by POE oils. Proper protective equipment (gloves, eye protection, etc.) must be used when handling POE lubricant. Handle POE oil with care. Refer to the Safety Data Sheet (SDS) for further details.
- Before energizing the system:
- Securely fasten the protective terminal cover or molded plug to the compressor, and
- Check that the compressor is properly grounded per the applicable system and compressor requirements.
Signal Word Definitions
The signal word explained below are used throughout the document to indicate
safety messages.
Principles of Cleaning Refrigeration Systems
Copeland strongly supports refrigerant recovery and recycling as part of the
solution to the CFC/ozone depletion problem. Only the latest techniques should
be used when servicing equipment containing CFCs.
Examination of compressors returned to the factory for replacement indicates
that many such replacements could have been prevented if all contaminants had
been removed from the refrigeration system at the time of field installation.
Returned compressors are at times reported as motor failures, but in reality
the return is due to damaged bearings, valve reeds, or connecting rods caused
by contaminants, which in turn caused motor damage as a secondary effect.
It is essential that all foreign materials be removed from the system at the
time of the original installation. Filings, shavings, dirt, solder, flux,
metal chips, bits of steel wool, sand from sandpaper, and wire from cleaning
brushes have all been found in systems and frequently end up in the
compressor. Many of these contaminants are so small they will pass through a
fine mesh screen. In addition, the metal fragments may be rotating because of
gas velocity and cut or break the usual compressor suction screen.
Suction Line Filter and Filter-Driers
As a result of the above types of contamination, a heavy-duty suction line
filter or filter drier is recommended for every field installation. These are
available with reasonable pressure drop, and will provide maximum protection
for the most vulnerable part of the system. A set of access valves should be
provided on the filter or filter-drier, to facilitate checking the pressure
drop.
An additional benefit of a suction line filter or filter-dripper is the added protection given the system if a burnout should occur. The filter will effectively prevent contamination resulting from the failure from traveling back through the suction line into the other parts of the system. An additional benefit of a suction line filter-drier is to capture any acid generated during the burnout before it causes any additional damage. This will minimize the contamination remaining in the system when the inoperative compressor is removed.
System Evacuation
Another important step in effectively cleaning a system before operation is
proper evacuation. Air is very detrimental to refrigeration systems and must
be removed before start up and after field service. Blowing out lines with dry
nitrogen may remove a major part of the air from a system, but if air is
trapped in the compressor during installation it is practically impossible to
remove from the compressor crankcase by purging with nitrogen.
New and replacement compressors are shipped from the factory with a dry air
holding charge, and must be evacuated before being put in service.
Triple evacuation of the system or compressor, as required, is strongly
recommended (twice to 1,500 microns and finally to 500 microns,) breaking the
vacuum each time with dry nitrogen. The vacuum pump must be connected to both
the high and low sides of the system through properly sized connections, since
restrictive service connections may make the process so slow as to be
unacceptable, or may lead to false readings because of pressure drop through
the fittings.
System Cleaning Procedure After Hermetic Motor Burn-out
When a motor burnout occurs in the compressor, the resulting high temperature
arc causes a portion of the refrigerant/oil mixture to break down into
carbonaceous sludge, corrosive acid, and water.
It has long been recognized that such contamination resulting from a burnout
can result in repeat failures if the contaminants are allowed to reach and
remain in the crankcase of the replacement compressor. This situation can be
prevented by following proper clean up procedures after a burnout.
Flushing out a refrigeration system with R-11 should not be considered since scientific evidence has linked ozone depletion to R-11 emissions. In case of a motor burn, Copeland recommends the filter-drier cleaning procedure. Basically this involves the use of approved filter-driers incorporating an adequate desiccant (not a filter only) in both the liquid and suction lines. This system cleaning procedure has been used in countless installations over the years, and when this procedure has been properly followed, we do not know of a single instance where after proper cleaning there has been a second failure.
The filter-drier procedure has proven to be very economical, especially when
the refrigerant in the system is recovered using safe recovery techniques.
This can be easily accomplished if the compressor is fitted with service
valves.
It is the only practical method we know of which can assure proper cleaning,
especially where long lines and multiple evaporators and circuits are
involved.
The size of the filter-driers (see Table 1) used to clean up the system should be such that the maximum pressure drop under normal operating conditions is within the limits shown. The connections on the filter-drier should normally be the same size as the connecting lines.
Exercise caution. Use rubber gloves and safety glasses and ventilate the work space. The oil from a burnout could cause serious skin irritation and possibly burns. In some cases, the fumes are toxic.
-
If possible, close the compressor service valves to isolate the compressor from the system. In order to avoid losing refrigerant to the atmosphere Copeland strongly recommends recovering refrigerant using standard recovery procedures and equipment. At that point, remove the inoperative compressor, and install the replacement.
-
Since the normal color of refrigerant oil varies from oil to oil, take a sample of oil from the replacement compressor and seal in a small glass bottle for comparison purposes after the cleaning operation is complete. Suitable two ounce bottles are obtainable at any drug store. If the compressor does not have service valves, see Step 6.
-
If the compressor has service valves, evacuate the compressor only, using the procedures previously outlined, since the rest of the system will be isolated. After evacuation, open the compressor service valves, close the liquid line valve, close any other available shut-off valves which will minimize the amount of refrigerant to be handled during pump-down, and pump the system down.
Although some contaminants will be returned to the compressor during the pump- down procedure, the compressor will not be harmed by the short period of operation required, and the contaminants will be removed as they are circulated through the system after the installation of the filter-driers. -
Inspect all system controls such as expansion valves, solenoid valves, check valves, reversing valves, contactors, etc. Clean or replace if necessary, remove all installed filter-driers and clean or replace any filters or strainers. Install an Copeland HMI or AMI moisture indicator to precisely monitor system moisture conditions if the system does not have one.
-
Install the recommended size Copeland suction line filter-drier and oversized Copeland liquid line filter-drier.
Go to Step 7. -
For systems without service valves, including refrigerant recovery, evacuate the system, following the procedures previously recommended. Perform the inspections and filter-drier changes listed in steps 4 and 5, and charge through a filter-drier with the refrigerant which was removed and recovered. Add additional refrigerant as necessary.
-
Start the compressor and put the system in operation. As the contaminants in the system are filtered out, the pressure drop across the filter-drier will increase. Observe the pressure differential across the filter-driers for a minimum of four hours, preferably by means of one gauge and a manifold to eliminate gauge error. If the pressure drop exceeds the maximum limits shown in Table 1 for a temporary installation, replace the filter-drier and restart the system.
-
After the completion of step 7, allow the unit to operate for 48 hours. Check the odor (warning, smell cautiously) and compare the color of the oil with the sample taken in step 2. Use of an Copeland Universal Acid Alert test kit is recommended to test for acid content. If the oil is discolored, has an acid odor, is acidic, or if the moisture indicator indicates a high moisture content in the system, change the filter-driers.The compressor oil can be changed if considered desirable. Allow the system to operate for an additional 48 hours, and recheck as before. Repeat until the oil remains clean, odor and acid free, and the color approaches that of the original sample.
-
Replace the liquid line filter-drier with an Copeland EK of the normally recommended size. Remove the suction line filter-drier and replace with permanent type suction line filter or filter-drier.
-
After the cleaning procedure is completed,recheck in approximately two weeks to ensure that the system condition and operation is completely satisfactory.
Table 1
Maximum Recommended Pressure Drop for Suction Line Filter-Drier PSI (bar)
The contents of this publication are presented for informational purposes only and are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. Copeland LP and/or its affiliates (collectively “Copeland”), as applicable, reserve the right to modify the design or specifications of such products at any time without notice. Copeland does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Copeland product remains solely with the purchaser or end user.