1. Safety
First:
Do Not Smoke While Performing
A/C Repair.
Do Not Drop Compressor.
Use Safety Goggles & Gloves While Handling Refrigerant.
2. Bring back old refrigerant using certified reclaiming equipment.
3. Remove old compressor from vehicle and transfer any switches or
brackets from old compressor to new compressor.
Note: On Ford products with an FS10 or an FX15 compressor that
has had a major failure, or GM products with a DA6 compressor with
broken Teflon rings and a dual path condenser, you must replace
the condenser.
4. Clean the A/C system with an approved flush solvent. R141b or Dura Flush is recommended. Do not use petroleum based solvents or alcohol.
Do not use flammable solvents. For proper flushing, you must disconnect hoses from items that
are not to be flushed.
Do flush:
All Hoses w/o Orifice Tubes or Muffler Assemblies
.
The Evaporator
.
The Condenser
.
Do Not flush:
The compressor.
The Accumulator or Receiver Drier
.
Hose assemblies w/either Filters or Muffler Assemblies
.
Expansion Valves
.
5. If system flushing with R141b or Dura Flush is not available, one
of two other methods must be followed. Either an in-line filter must be installed in the high side of
the A/C system or the system must be cleaned using power flush
equipment.
6. If an in-line is used in place of flushing, oil charging must be
handled differently and carefully
Drain all of the old oil out
of the old compressor into a graduated cylinder.
Drain as much oil out as possible, rotate the compressor if
necessary.
Record amount of oil, if it is less than one (1) oz. (34
milliliters), then add 2 oz. (68 milliliters) of new oil to the new
compressor through the suction port.
If the amount is over one (1) oz. (34 milliliters), add the same
amount drained through the suction port of the compressor.
Accumulator (must be replaced) : Drain the old lubricant from the
old drier or accumulator. Add the same amount drained, plus two (2)
additional oz. (68 milliliters) to the new accumulator/ filter drier.
Evaporator (option) : Add three (3) oz. (100 milliliters) to the
new evaporator.
Condenser (option) : Add one (1) oz. (34 milliliters) to the new
condenser.
Be sure not to over oil or under oil the A/C system using this
method. It may cause system
failure.
7. The receiver drier or accumulator drier must be replaced.
8. The orifice tube at evaporator inlet, condenser outlet or in
liquid line must be replaced (if the vehicle is so equipped).
9. The thermostatic expansion valve must be inspected for debris or
metal particles. Any
restrictions will lead to poor performance or premature compressor
failure.
10. Make sure you have clear air flow through the A/C condenser and
the vehicle’s radiator. Clean
all bugs and debris off the condenser. Check coolant LEVEL AND CONDITION. Inspect air dams and condenser/radiator seals.
Note : On Ford products with an FS10 or an FX15 compressor that
has had a major failure, or GM products with DA6 compressor with broken
Taflon rings and a dual path condenser, you must replace the
condenser.
11. Check fan clutch or electric fan for proper operation. Inspect fan hardware and mounting. Inspect fan blades for cracks and loose mounting.
12. Check the compressor clutch air gap before installation. The gap is pre-set at the factory, however it may become out of
adjustment during shipping and handling. Failure to check gap may lead to premature clutch failure. Refer to OEM specifications or the enclosed specification sheet
from the manufacture.
13. The proper amount and correct type of lubricant are critical. CFC12 systems use mineral oil and HFC134a systems use
polyalkylene glycol (i.e.PAG) or polyol ester (i.e. POE, ester) lubricants. Lubricants are not cross-compatible and cannot be substituted for
each other. Refer to the
Original Equipment Manufacture’s specifications enclosed with the
compressor for proper oil charges.
14. It is recommended that the oil charge be spit between various
locations in the vehicle’s A/C system. An equal portion of the total oil charge should be placed into the suction side of the compressor and accumulator or receiver
drier. This will ensure
proper oil flow through the A/C system and the compressor during system
start-up.
15. When mounting the compressor onto the vehicle, tighten all
mounting bolts evenly and DO NOT over tighten. DO NOT use an impact wrench. The aluminum cases on many compressors can easily be warped or
distorted. Failure to do
this may cause premature compressor failure. Refer to OEM specification sheet from the manufacturer. Lubricate all fittings and seals with mineral oil or o-ring lube,
even when retrofitting.
16. Once the compressor is mounted onto the vehicle and hoses are
connected, the compressor shaft (not just the compressor clutch pulley)
must be rotated a minimum of 10 times. This is to clean the lubricant from the cylinders. Failure to correctly perform this procedure will cause premature
compressor failure. In many instances a spanner wrench will be needed for the
procedure. DO NOT turn the
compressor clutch nut, you may inadvertently change the clutch air gap. This too many cause premature clutch failure.
17. IT is now time to evacuate the system of moisture and air. Using an approved vacuum pump, evacuate the A/C system to 29.5 in/Hg for a
minimum of 45 minutes if the
temperature is over 80 degrees Fahrenheit
Sixty (60) minutes are recommended when the vehicle is equipped
with dual A/C or when the temperature is 80 degrees Fahrenheit or less.
18. Recharging the system is next. Remember, only R12 or R134a are approved refrigerants for the
compressor. Only R12 will
maintain system integrity and compressor warranty. The use of an unapproved refrigerant will automatically void the
compressor warranty. Use a
scale or meter to charge with refrigerant. DO NOT charge by gauges alone. The correct charge of R12 or R134a is critical for proper
performance. If then
replacement charge is replacing a like refrigerant, use the recommended
OEM charge. If the compressor is being utilized in a retrofit to R134a,
please refer to either the Original Equipment Manufacturers’ or
compressor manufacturers’ retrofitting procedures. If the vehicle is being retrofitted, DO NOT charge the system to
the capacity listed for
R12 as it will automatically overcharge the
system, resulting in elevated high side pressures and probable premature
compressor failure.
19. It is important to check the compressor clutch electrical
circuit. Use a volt meter to check for proper clutch voltage.
If the proper voltage is not found, it may cause premature clutch
failure. (Check OEM specifications for proper voltage.) It
is recommended that the clutch be burnished to increase the grip between
the compressor clutch plates. With the engine at approximately
2000 RPM, cycle the compressor clutch off and on twenty times using the
A/C control switch on the dash. This will enhance compressor and
compressor clutch performance.
Note:
If the A/C system has experienced a catastrophic compressor
failure, the condenser should immediately be suspect for replacement. If a pyrometer is available, the inlet and outlet should be
checked for a dramatic drop in temperature. Anything over a 60-degree drop between the inlet and outlet
indicates that either further flushing of the condenser is needed or
condenser replacement may be required.
Refrigerant seepage around
the compressor shaft seal is normal for the first few hours of
operation.
