Thermo King KD-II SR, Manual

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Refrigeration Service Operations (Rev. 04/03)
120
Compressors Shipped with R-134a
The KD-II SR compressors are Thermo King compressors
and are charged with Polyol Ester oil (POE) (TK No.
203-413). All gauge fittings are 1/4 inch fittings.
CAUTION: POLYOL ESTER (POE) IS THE
ONLY OIL FOR USE WITH THERMO KING
UNITS USING R-134a AND R-404A. IT SHOULD NOT
BE ADDED TO STANDARD THERMO KING UNITS,
NOR SHOULD THE STANDARD OR SYNTHETIC OIL
BE ADDED TO SYSTEM CONTAINING R-134a AND
R-404A. COMBINING THE TWO OILS COULD
RESULT IN DAMAGE TO THE SYSTEM.
Because Polyol Ester has an affinity for moisture, it must be
kept in capped containers. In addition, it should be added as
the last step in system repair. Rubber gloves are recom-
mended when handling Polyol Ester because it may cause
skin irritation.
EQUIPMENT RECOMMENDATIONS FOR
USE WITH R-134a AND R-404A
Dedicated Equipment
CAUTION: Equipment that has been used with
other refrigerants MUST NOT be used with R-134a
and R-404A refrigerants. Mixing R-134a and R-404A with
other refrigerants will cause contamination of the refrig-
erant. Using contaminated refrigerant will cause system
failure.
Vacuum Pumps
When evacuating a two stage, three or five CFM pump is
recommended. It is also recommended that dry nitrogen be
used first. Ideally, a new vacuum pump should be used and
dedicated for use with R-134a or R-404A systems because
residual refrigerants may remain in used vacuum pumps.
Pumps used with other Thermo King refrigerants may be
used but extreme care should be taken to prevent contami-
nation of R-134a or R-404A systems with other refrigerants.
An oil filter, P/N 66-7462 is added.
The Thermo King Evacuation Station is recommended. This
station is available from service parts under part number
204-725. See Truck and Trailer Service Bulletin T&T 061
for additional details.
Use only recommended vacuum pump oils and change oil
after every major evacuation. Vacuum pump oils are highly
refined and the use of contaminated oils will prevent the
desired vacuum from being obtained. Failure to follow these
recommendations may result in conditions that will destroy
the vacuum pump.
Gauge Manifold Sets
Gauge manifold sets that show the correct pressure-temper-
ature relationship should be used. Gauge manifolds and
manifold hoses used with other Thermo King refrigerants
may be used but extreme care should be taken to prevent
contamination of the R-134a and R-404A systems with
other refrigerants. Purge manifold and hoses with dry nitro-
gen before using. NEVER USE EQUIPMENT THAT MAY
BE CONTAMINATED WITH AUTOMOTIVE TYPE
POLYALKYLENE GLYCOL (PAG) OILS.
System Clean-up
Existing clean up devices such as suction line filters and
compressor oil filters may be used if they are thoroughly
cleaned and new filter elements are installed. All standard
compressor oils must be removed from clean-up devices to
prevent contamination of R-134a and R-404A systems.
Dangerous contamination will result if other refrigerants or
standard oils are introduced to R-134a or R-404A systems.
NOTE: For additional information on parts and supplies,
consult your local Thermo King dealer and Thermo King
Tool Catalog TK No. 5955.