EVAPORATOR COIL, MALE COUPLING HALF AND EXPANSION VALVE - continued

TM9-4120-423-14&P

TEST AND INSPECTION

Unwrap the insulation from the evaporator coil suction line so that thermal sensing bulb is

exposed.

Loosen the screws and nuts in the bulb straps that attach the sensing bulb to the suction line, and

pull the bulb out of the straps. Take care to note the position (center top of suction line) of the

bulb.

CAUTION

Use care to not damage or kink the capillary.

Connect a remote control module and a power cable to the air conditioner.

WARNING

AC power tests must be conducted with the power on. Exercise extreme caution.

Turn on power to air conditioner.

Place the sensing bulb in a container of ice water or crushed ice so that it is reduced to a

temperature near 32Ε F (0Ε C).

Set the temperature thermostat control knob fully counterclockwise to COOLER position, place

one hand on the exposed suction line, and start the air conditioner in COOL mode. If a drop in

temperature is felt on the suction return line, the expansion valve is not closing fully and should

be adjusted or replaced.

CAUTION

Turn the air conditioner to OFF as soon as a definite drop in temperature is felt on the

suction return line. If the test conditions are continued more than a few seconds, the

expansion valve will fully open and an excessive flood-back of liquid Refrigerant R-22

may damage or destroy the compressor.

With one hand still on the suction return line, remove the sensing bulb from the container and

warm it in the other palm. If a temperature drop is not felt in the suction return line by the time

the sensing bulb no longer feels cold to the hand, the expansion valve is not opening and should

be adjusted or replaced. As soon as a temperature drop is felt, turn the air conditioner to OFF.

END OF TASK

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