TM 5-3805-290-23-1
AIR CONDITIONING SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0018 00
REFRIGERANT QUICK-CHECK PROCEDURE FOR R-134A EXPANSION
VALVE AND ORIFICE TUBE SYSTEMS - CONTINUED
0018 00
5.
If system has no refrigerant charge or if system is nearly empty of refrigerant charge, perform the following procedure:
a.
Stop engine (TM 5-3805-290-10).
b.
Perform a partial charge of system (WP 0191 00).
c.
Perform a leak test. Refer to Refrigerant Leakage Test in this work package.
d.
Repair leaks.
e.
Evacuate system (WP 0191 00).
f.
Charge system with correct amount of refrigerant. Measure refrigerant by weight (WP 0191 00).
g.
Perform a performance check. Refer to Performance Checks for Air Conditioning System in this work package.
N OT E
Refer to Table 1.
6.
An overcharge of system is possible even though system can have a definite difference in temperature at low pressure
line and at high pressure line.
a.
Recover refrigerant (WP 0191 00).
b.
Evacuate system (WP 0191 00).
N OT E
All pressures are given as a guide only. Weight is only absolute means of determining proper refrigerant
charge. Improper refrigerant charge will cause premature failure of compressor.
Table 1. Pressure Range.
HIGH PRESSURE TEST FITTING
(PRESSURE MAY BE SLIGHTLY
HIGHER IN VERY HUMID
LOW PRESSURE TEST FITTING
CONDITIONS AND LOWER IN
(PRESSURE BEFORE CLUTCH
AMBIENT AIR TEMPERATURE
VERY DRY CONDITIONS)
DISENGAGEMENT)
70F (21C)
120 to 190 psi (820 to 1,300 kPa)
10 to 20 psi (70 to 138 kPa)
80F (27C)
140 to 210 psi (950 to 1,450 kPa)
10 to 25 psi (70 to 173 kPa)
90F (27C)
170 to 240 psi (1,175 to 1,650 kPa)
15 to 30 psi (105 to 210 kPa)
100F (38C)
190 to 270 psi (1,300 to 1,850 kPa)
15 to 30 psi (105 to 210 kPa)
110F (43C)
210 to 300 psi (1,450 to 2,075 kPa)
15 to 30 psi (105 to 210 kPa)
c.
Charge system with correct amount of refrigerant. Measure refrigerant by weight (WP 0191 00).
d.
Perform a performance check. Refer to Performance Checks for Air Conditioning System in this work package.
e.
Determine level of system charge. When both inlet of accumulator and outlet of accumulator are cool to touch, sys-
tem is charged correctly.
0018 00-5
