Johnson Controls York MaxE YK Series, Руководство пользователя

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JOHNSON CONTROLS
FORM 160.75-O1 (309)
24
troubleshooting
section 6
maintenance
reneWal parts
For any required Renewal Parts, refer to YORK Renewal
Parts Unit Components Manual 160.75-RP1.
checKing sYstem for leaKs
leak Testing During Operation
The refrigerant side of the system is carefully pressure
tested and evacuated at the factory.
After the system has been charged, the system should
be carefully leak tested with a R-134a compatible leak
detector to be sure all joints are tight.
If any leaks are indicated, they must be repaired im-
mediately. Usually, leaks can be stopped by tightening
flare nuts or flange bolts. However, for any major repair,
the refrigerant charge must be removed. (See “Handling
Refrigerant for Dismantling and Repair”, page 29.)
conducting r-22 pressure test
With the R-134a charge removed and all known leaks
repaired, the system should be charged with a small
amount of R-22 mixed with dry nitrogen so that a halide
torch or electronic leak detector can be used to detect
any leaks too small to be found by the soap test.
To test with R-22, proceed as follows:
1. With no pressure in the system, charge R-22 gas into
the system through the charging valve to a pressure
of 2 PSIG (14 kPa).
2. Build up the system pressure with dry nitrogen to ap-
proximately 75 to 100 PSIG (517 to 690 kPa). To be
sure that the concentration of refrigerant has reached
all part of the system, slightly open the oil charging
valve and test for the presence of refrigerant with a
leak detector.
3. Test around each joint and factory weld. It is impor-
tant that this test be thoroughly and carefully done,
spending as much time as necessary and using a good
leak detector.
4. To check for refrigerant leaks in the evaporator and
condenser, open the vents in the evaporator and con-
denser heads and test for the presence of refrigerant.
If no refrigerant is present, the tubes and tube sheets
may be considered tight. If refrigerant is detected at the
vents, the heads must be removed, the leak located (by
means of soap test or leak detector) and repaired.
eVacuation and dehYdration of unit
fig. 9 – EVACuATION OF CHILLER
27385A(D)
LD00949