A/C SYSTEM PERFORMANCE TEST
WARN I N G
This system is under pressure at all times, ev n if the engine is not running. Heat should
never be applied to a charged system.
Contact with refrigerant can cause frostbite. Keep face and hands away.
Protective goggles must always be worn when refrigerant lines are opened, even if the
gauges indicate the system is empty of refrigerant.
Always use caution when a fitting is removed.Slowly loosen the fitting. If the system is still
under pressure, evacuate the system recovering the refrigerant before removing the
Do not smoke when servicing air conditioners or wherever refrigerant gas may be present.
Before any checks of the air conditioning and heating system are made, move the
machine to a smooth horizontal surface. Lower all implements to the ground. Make sure
the machine is in neutral or park and that the parking brake is engaged. Keep all other
personnel away from the machine or where they can be seen.
Failure to follow these warnings may result in injury or death to personnel.
N OT E
Ambient temperature must be at least 70°F (21°C) in order to conduct A/C performance
1. Inspect fresh air filter and recirculation air filter, and replace if dirty or damaged (TM 5-3805-293-10).
2. Inspect condenser. Clear away anything that will obstruct airflow such as dirt, debris, insects, etc.
3. Inspect refrigerant lines and hoses.
a. Inspect for damage from excessive heat or rubbing. Replace refrigerant lines and hoses if damage found
b. Inspect for oily surfaces along hose and coupling connections. This can indicate refrigerant leak. Replace
refrigerant lines and hoses if oily surfaces are found (WP 0296).
4. Turn battery disconnect switch ON (TM 5-3805-293-10).
5. Start and run engine at idle speed (TM 5-3805-293-10).
6. Set cab temperature control knob to MAXIMUM cool position (TM 5-3805-293-10).
7. Turn air conditioning ON (TM 5-3805-293-10).
8. Set HVAC fan speed switch to HIGH position (TM 5-3805-293-10).
9. After 10 to 15 minutes of operation, adjust engine speed to approximately 1,300 to 1,400 rpm (TM 5-3805-293-