- Caterpillar Products: equipped with 3E-3535 In-Line Refrigerant Dryer
- All
Reference: See Service Magazine, 24 May 1999, Page 9, "Air Conditioner Service Tips".
Reference: Service Manual Module, SENR5664-05, "Air Conditioning and Heating".
Description of Change: The in-line refrigerant dryer in the air conditioner system is improved. The factory installed dryer features the improvements that follow: improved air conditioner quick disconnects, a tracer dye wafer in the air conditioner desiccant and the removal of the moisture indicator.
A new air conditioner dryer is available for service replacement. The new dryer does not contain the tracer dye wafer in the air dryer desiccant cartridge. Additional dye is not required after repairs are completed for system leaks or component replacement. The air conditioner system contains a sufficient amount of dye.
Adaptable To: The new 175-7162 Dryer is the service replacement for the 3E-3535 In-Line Refrigerant Dryer. The elimination of the tracer dye wafer is the only difference between the two dryers. Both dryers are compatible with R-12 refrigerant and with R-134a refrigerant.
New dye must be added to the system whenever the system is flushed. Only use a dye that is supplied by Caterpillar. Dyes with a solvent base and dyes with a mineral oil base can cause the problems that follow: an a/c compressor failure and the formation of a sludge deposit in the air conditioner system.
System leaks that are indicated by the presence of a dye should always be confirmed with an electronic leak detector. The dye can be removed by using a water base oil solvent or a general purpose cleaner.
The maintenance methods for the R-12 refrigerant system are not compatible with the maintenance methods for the R-134a refrigerant system. The R-134a system will normally have a small amount of frost at the dryer outlet port.
Comply with the procedure in the Service Manual Module, SENR5664-04, "Air Conditioning and Heating" in order to replace the dryer of a R-134a refrigerant system. Compliance with the procedure will provide the benefits that follow:
- The refrigerant compressor oil will not escape from the system.
- The amount of moisture that enters the system will be reduced.
- A sludge deposit will not form.
- It will not be necessary to top off the system with compressor oil or refrigerant.
Note: The R-134a refrigerant dryer should be replaced annually. Extremely humid operating conditions may require more frequent replacement of the dryer. The dryer should also be replaced if the air conditioning system has been leaking or if the system has been opened for service repair.