Service Contractors: Attention Please - True GDM Series Technical & Service Manual

SERVICE CONTRACTORS
..... ATTENTION PLEASE .....
..... ATTENTION PLEASE .....
This is a Tecumseh hermetic compressor specifically designed for use with environmentally
friendly HFC refrigerant R404A. However, it is acceptable to use this compressor as a service
replacement with R502.
The Tecumseh approved polyolester (POE) oil contained in this compressor is compatible
with all internal component materials and is miscible (mixes) with R502 to effect proper oil
return. Using R502 with this R404A compressor will result in very similar performance to
the replaced R502 compressor. But, the following precautions should be taken.
1) Care must be taken to assure that most of the mineral oil is removed from the system
before the new compressor is installed. Small amounts of mineral oil (up to 5%) left in
the system are acceptable but 1% or less if achievable is desired.
2) POE oils are 100 times more hygroscopic (ability to absorb moisture) than mineral oils
thus the utmost care must be taken to prevent moisture from entering the system. The
compressor or system should not be left open to the atmosphere for longer than 15 min-
utes maximum.
3) The appropriate new drier provided must be installed in the system.
4) Established industry procedures for recovery, evacuation, refrigerant charging and leak
testing should be followed.
SERVICE CONTRACTORS
TRUE MANUFACTURING COMPANY
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