Thermo King UT-1200, Руководство пользователя

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Refrigeration Service Procedures
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NOTE: To check certain components, front seat
the suction service valve to isolate the low side
while it is still in a vacuum. See “Refrigeration
System Checks” and the individual component
tests for more information.
4. Turn the unit Off.
5. Prepare to perform service on the low side by
raising the low side pressure through the
gauge manifold to 1 to 2 psig (7 to 14 kPa).
6. Front seat the suction service valve to isolate
the low side. The discharge check valve in the
compressor is an imperfect seal and will not
keep the discharge pressure from leaking back
through the compressor. Use the suction
access port located near the accumulator inlet
to access the low side for leak testing and
evacuation.
7. Back seat the suction service valve and then
the receiver tank outlet valve. Perform a
“Refrigerant Gauge Removal” procedure.
R404A
These units use R404A. This refrigerant is
classified as a Hydro-fluorocarbon (HFC) because
it contains hydrogen fluorine and carbon. It does
not contain chlorine.
Unit Identification
Units charged with R404A are identified by the
following methods:
1. R404A will be stamped on the unit’s serial
plate.
2. Decals will be applied to unit as shown below:
Figure 199: R404A Decal
Availability
R404A is available from wholesalers. The price
will depend upon the quantity purchased. Thirty
(30), 50 and 125 containers are available.
Leak Detection
Leaks can be detected by an electronic leak
detector such as the G.E. H10G or a portable leak
detector (see Tool Catalog). See Truck and Trailer
Service Bulletin T&T 048 for additional details.
Compressor Oil
Thermo King Corporation has chosen to use a
compressor oil called Polyol Ester (POE)—also
called ester based oil. POE oil is compatible with
R404A and can be used in low temperature
applications. This oil is available from service
parts (P/N 203-516).
Required for Scroll
compressors.
Compressors Shipped with POE Oil
Thermo King Scroll compressors are charged with
Polyol Ester oil (POE). All gauge fittings are
1/4 inch fittings.
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 recommended when handling
Polyol Ester because it may cause skin irritation.
Equipment Recommendations For
Use With R404A
Dedicated Equipment
AEA648
CAUTION: POLYOL ESTER (POE) IS
THE ONLY OIL FOR USE WITH
THERMO KING UNITS USING R404A.
IT SHOULD NOT BE MIXED WITH
ANY OTHER TYPE.
CAUTION: Equipment that has been used
with other refrigerants MUST NOT be
used with R404A refrigerants. Mixing
R404A with other refrigerants will cause
contamination of the refrigerant. Using
contaminated refrigerant will cause
system failure.