TM 5-2420-230-24-1
The A/C system must contain at least 0.88 lb. (0.4 kg) of refrigerant. The manifold gage set can
determine if pressure exists in the system.
Leaks that are in the high side of the A/C system are more easily found if the air conditioner is
operated for 5 to 10 min. The leak test must be performed immediately after the unit is turned off.
The leak test for the high side needs to be performed before the pressure in the A/C system
equalize.
Leaks that are in the low side of the A/C system are more easily found if the air conditioner has
been shut off for 5 to 10 min. The leak test for the low side needs to be performed before the
pressure in the A/C system equalize.
(1)
Move leak detector sensor tip along possible leak points, at a rate of one inch per second.
(2)
Leak detector will notify mechanic if leak is present in A/C system.
b. Recovery.
If service is required on the air conditioning system, refrigerant must be recovered before A/C system components are
removed. Use the following procedure:
NOTE
Refrigerant identifier will prevent other refrigerants from contaminating R-134a recovery and
charging tools. Refrigerant identifier will also detect a percentage of air that may be in the A/C system.
(1)
Use refrigerant identifier to ensure refrigerant in A/C system is R134a
(2)
Make sure that both manifold gauge set (1)
valves (2) and (3) are closed. Turn valves (2)
and (3) clockwise to close.
Contact with refrigerant can cause
frostbite. Keep hands and face away to
prevent personal injury.
Protective goggles must always be worn
when refrigerant lines are opened, even if
the gauges indicate the system is empty.
Do not smoke when servicing air
conditioners or wherever refrigerant gas
may be present. Personal injury or death
can result from inhaling refrigerant
through a lit cigarette.
(3)
Install manifold gage set (1) low-side hose (4) to suction (low) side of A/C compressor.
(4)
Install manifold gauge set (1) high-side hose (5) to discharge (high) side of A/C compressor.
