Overcharged Refrigerant Systems - Friedrich VERT-I-PAK VHA09K25RTQ Service Manual

R-410A SEALED SYSTEM REPAIRS

Overcharged Refrigerant Systems

RISK OF ELECTRIC SHOCK
Unplug and/or disconnect all electrical power
to the unit before performing inspections,
maintenances or service.
Failure to do so could result in electric shock,
serious injury or death.
HIGH PRESSURE HAZARD
Sealed Refrigeration System contains refrigerant
and oil under high pressure.
Proper safety procedures must be followed,
and proper protective clothing must be worn
when working with refrigerants.
Failure to follow these procedures could
result in serious injury or death.
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WARNING
WARNING
NOTE: Ensure fan is on high speed during testing.
NOTE: A unit sealed from the factory will not be overcharged.
Whenever an overcharged system is indicated, always make sure
that the problem is not caused by air flow problems. Improper air
flow over the evaporator coil may indicate some of the same symp-
toms as an over charged system.
NOTE: Factory sealed units will not be overcharged
An overcharge can cause the compressor to fail, since it
would be "slugged" with liquid refrigerant.
The charge for any system is critical. When the compressor
is noisy, suspect an overcharge, when you are sure that the
air quantity over the evaporator coil is correct. Icing of the
evaporator will not be encountered because the refrigerant
will boil later if at all. Gauges connected to system will
usually have higher head pressure (depending upon amount
of over charge). Suction pressure should be slightly higher.
Compressor amps will be near normal or higher. Non-
condensables can also cause these symptoms. To confirm,
reclaim some of the charge, if conditions improve, system
may be overcharged. If conditions don't improve, Non-
condensables are indicated.