ARMY TM 9-4120-380-14
NAVY EE-000-BA-MMA-010/7053-AC
AIR FORCE TO 35E9-136-21
5.16. REFRIGERANT PRESSURE CHECK. This task covers service.
INITIAL SETUP
Tools
Tool kit, service, refrigeration unit (Item 1, Appendix B)
Gloves, chemical (Appendix C)
Goggles, industrial (Appendix C)
Personnel:
1
SERVICE
Death or serious injury may result If personnel fail to observe safety precautions Use
great care to avoid contact with liquid refrigerant or refrigerant gas being discharged
under pressure. Sudden and irreversible tissue damage can result from freezing. Wear
thermal protective gloves and a face protector or goggles in any situation where skin-
eye-contact is possible.
Prevent contact of refrigerant gas with flame or hot surfaces Heat causes the refrigerant
to break down and form carbonyl chloride (phosgene), a highly poisonous and corrosive
gas.
a. Except in cases where it is obvious that the refrigerant charge has been lost, the first step in troubleshooting
problems in the refrigeration system should be to check discharge and suction pressures under operating
conditions.
b. Check pressures as follows:
(1)
Turn MODE SELECT switch to OFF
(2)
Connect service manifold (paragraph 5.9).
(3)
Open CGV and PGV. Both manifold gauges should read the same. Check the reading with the
appropriate column in table 5-1. If the system is even partially charged, the pressure should be
approximately equal to that shown in the table for the appropriate ambient temperature. If the
pressure is considerably less than shown in the table, the system does not contain enough refrigerant
to continue the pressure check, go to leak testing (paragraph 5.13).
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