TM 9-4120-401-14
5-20. OVERHEATING CHECKS.
This task covers:
Examine
INITIAL SETUP
Equipment Condition
Unit operating in full COOL.
Examine.
NOTE
Bubbles appearing in the sight glass or a reduction in cooling capacity is often
caused by the refrigeration system being overheated. Adequate cooling of the
hot, compressed, refrigerant vapor in the condenser is essential to the proper
operation of the air conditioner.
Painting coils will cause overheating and reduce cooling capacity.
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:
(a) Be sure there is no external obstruction to air flow into the condenser intake screen and out of the
condenser fan guard.
(b) Be sure there is no obstruction within the intake screen and fan guard.
(c) Be sure there are no obstructions or an excessive build-up of dust and dirt in the condenser coil.
(d) Turn rotary MODE selector switch to OFF/RESET.
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