This task covers:
Tool kit, service, refrigeration unit
Power off at power source.
Both front door assemblies removed. See para 4-17.
General Safety Instructions:
Disconnect input power to the air conditioner before performing any internal
maintenance. Voltages used can kill. Shutting the unit off at the control panel
does not disconnect unit power.
Avoid skin contact or inhaling fumes from any acid formed by burnout of oil and
refrigerant. Wear a gas mask if area is not thoroughly ventilated. Wear protective
goggles or glasses to protect eyes. Wear rubber gloves to protect hands.
Tag and remove the wiring from the compressor terminals (1, Figure 5-10) and check for ground between
(2) Check for continuity between the common terminal (C) and the run terminal (R) and between common terminal
(C) and start terminal (S). (Make sure the compressor is cool to the touch; the internal overload may be open.)
(3) Check the shorts/opens between winding turns with a multimeter.
Common to Start should read 1 to 5 ohms.
Start to Run should read 1 to 5 ohms.
Smell cautiously; the gas could be toxic and highly acid.
Sample the smell of the refrigerant gas at the suction port for the characteristic acrid odor of a burnout. If the
system has a burnout, go to step (6). If there is no odor of a burnout, go to step (5).
If the above steps check OK, look elsewhere for the trouble. The external electrical components are a good