OVERHEATING CHECKS.

TM5-4120-383-14

OVERHEATING CHECKS.

5-18.

Overheating of the refrigeration system is often the cause of

bubbles appearing in the sight glass, or a reduction in cooling

Adequate cooling of the hot, compressed refrigerant

capacity.

vapor in the condenser is essential to the proper operation of the

air conditioner. The following checks should be made to ensure

that overheating is not the cause of the symptoms before

troubleshooting the pressurized portion of the refrigeration

system:

Be sure there is no external obstruction to air flow into

the condenser intake screen and out of the condenser fan guard.

Be sure there is no obstruction within the intake screen and

fan guard.

Be sure there are no obstructions or an excessive build-up

of dust and dirt in the condenser coil.

NOTE

Addition of paint on coils will cause an insulation

and retardation of heat transfer.

REFRIGERANT PRESSURE CHECK.

5-19.

Except in cases where it is obvious that the refrigerant charge has

been lost, the first step in troubleshooting problems in the

refrigeration system should be to check discharge and suction

Check pressures as follows:

pressures under operating conditions.

Turn MODE SELECTOR switch to OFF.

Remove charging valve access cover.

c. Connect individual pressure gages or a refrigeration

servicing manifold and hoses to high (discharge) and low (suction)

charging (service) valves.

Take care that only a very small amount of

refrigerant is allowed to escape during hose purging.

Loosen hose connections at gages or charging

manifold.

5-42