Overcharged Refrigerant Systems - Friedrich PTAC ZONEAIRE SELECT Service & Parts Manual

R-410A SEALED SYSTEM REPAIRS
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.
Figure 602 (Overcharged System)
44
WARNING
WARNING

Overcharged Refrigerant Systems

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 symptoms as an over
charged system.
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.
Noncondensables can also cause these symptoms.
To confirm, reclaimsome of the charge, if conditions
improve, system may be overcharged. If conditions
don't improve, Noncondensables are indicated.