19-4. A/C SYSTEM SERVICING.
This Task Covers:
a. Leak Test
e. Follow-On Maintenance
TM or Para
Vehicle positioned on level
Tools and Special Tools
Parking brake applied.
Engine shut OFF.
Tool kit, refrigeration equipment, Item 39, Appendix B
Electrical master switch OFF.
"Do Not Operate" tag attached
to ignition switch.
MOS 52C, Utilities Equipment Repairer
Estimated Time to Complete Task
Replace receiver-drier if one or more of the following conditions occur before you purge A/C system:
A/C system has been previously opened for service
Too much air or moisture in A/C system
Receiver-drier has been operated for 2 or more years
A/C system opened for longer than 5 min.
Large A/C system leak (break in hose or line)
a. Leak Test.
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.
Always use caution if a fitting is removed. Slowly loosen the fitting. If the system is still under
pressure, release it slowly in a well-ventilated area.
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.
If service work is required on an A/C system, the refrigerant must be recovered first before
components are removed.