Section 6 - Maintenance; Renewal Parts; Checking System For Leaks; Conducting Pressure Test - York R-134a Operation And Maintenance Manual

FORM 160.76-O1
ISSUE DATE: 05/22/2019

RENEWAL PARTS

Please order all replacement parts at
tor.com (see Figure 10).

FIGURE 10 - PARTS NAVIGATOR

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 compatible leak detector
to be sure that all joints are tight.
CHARGING VALVE
WET BULB TEMPERATURE
INDICATOR OR VACUUM GAUGE

FIGURE 11 - EVACUATION OF CHILLER

JOHNSON CONTROLS

SECTION 6 - MAINTENANCE

www.hvacnaviga-
LD28095
EVACUATION AND DEHYDRATION OF UNIT
If any leaks are indicated, they must be repaired im-
mediately. Usually, leaks can be stopped by tighten-
ing flare nuts or flange bolts. However, for any major
repair, the refrigerant charge must be removed. (See
Handling Refrigerant For Dismantling And Repairs
on page 28)

CONDUCTING PRESSURE TEST

With the refrigerant charge removed and all known
leaks repaired, the system should be charged with a
small amount of refrigerant mixed with dry nitrogen so
that electronic leak detector can be used to detect any
leaks too small to be found by the soap test.
To test with refrigerant, proceed as follows:
1. With no pressure in the system, charge refrigerant
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
approximately 75 psig to 100 psig (517 kPa to 690
kPa). To be sure that the concentration of refriger-
ant has reached all parts of the system, slightly
open the oil charging valve and test for the pres-
ence of refrigerant with a leak detector.
27385A(D)
STOP VALVE
VACUUM PUMP
6
LD00949
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