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.