CSR-20 & CSR-40, September 1999
Refrigeration System Diagnosis and Service
Refrigerant Charge
6-5
Refrigerant Charge
NOTE: CSR Hermetic units do not have service
valves, fittings or sight glasses installed in the refrig-
eration system. Therefore, the refrigerant charge
level can not be visually inspected.
Perform a controller Pretrip Test to determine that a CSR
Hermetic refrigeration system contains an adequate charge of
refrigerant for cooling. If the unit passes the the Pretrip Test,
the refrigerant charge is OK.
A Pretrip Test should be performed during pretrip and
routine maintenance inspections. A low charge of refrigerant
will cause the container temperature to rise due to the lack of
liquid refrigerant at the expansion valve even though the unit
is operating in a cooling mode. The unit is charged with 4.1
kg (9.0 lb) R-404A refrigerant at the factory.
Unit Refrigerant Charge:
• Standard receiver: 4.1 kg (9.0 lb) of R-404A.
• Water-cooled condenser-receiver: 5.0 kg (11.0 lb) of R-
404A.
NOTE: Inspect the unit for refrigerant leaks with a
reliable leak detector if the unit is suspected of being
low on R-404A charge.
CAUTION: When adding R-404A to the unit, be care-
ful not to OVERCHARGE the unit.
Compressor Oil Charge
CSR Hermetic units do not have service valves, fittings or
sight glasses installed in the refrigeration system. Therefore,
the compressor oil level can not be visually inspected. To
maintain the correct compressor oil level in the unit:
1.
Whenever possible, drain and measure the compressor oil
from major system components that are removed for ser-
vice or replacement whenever possible. Major compo-
nents include:
- Compressor
- Filter drier
- heat exchanger
- Receiver tank
- Water-cooled condenser-receiver tank
NOTE: If the compressor oil is discolored, per-
form a compressor oil acid test (oil test kit P/N
203-457). If the compressor oil shows an acid
condition, change the oil, the filter drier and per-
form a refrigeration system cleanup.
2.
Add an amount of new compressor oil equal to the amount
removed from the old component. Use only Polyol Ester
compressor oil, P/N 203-433.
CAUTION:
• Use ONLY Polyol Ester based refrigeration
compressor oil, P/N 203-433.
• DO NOT mix Polyol Ester based and standard
synthetic compressor oils.
• Rubber gloves are recommended when han-
dling Ester based compressor oil.
• Keep Polyol Ester based compressor oil in
tightly sealed containers. If Ester based oil
becomes contaminated with moisture or stan-
dard oils, dispose of properly — DO NOT USE!
