WP25
Refrigeration compressor motor has built-in thermal
and current overload protection but circuit should be
fused. To confirm that the drier is powered and operating,
observe the condensor fan either through the condensor
or from the rear. To confirm that the refrigeration com-
pressor is actually running, on models prior to Sept. 1974,
you will have to reach in from the rear and feel the
hermetic. On larger models you should feel a slight
vibration as well as warmth. A green light indicates proper
cooling. The light is wired to a thermal switch in the unit.
Drier must be wired to run continuously when the
compressor i s in service a n d should not cycle on
If discharge outlet is not cold, but unit is properly
wired and running, the drier may have lost its refrigerant
charge. If not running, check electrical circuit to be sure
the unit is receiving the correct power supply (see name
plate).
Feel condensate discharge outlet ahead of trap and as
close to drier as possible. The outlet should be cool to
the touch, about 40 to 45 F, under all operational con-
ditions (no flow to full capacity flow of compressed air).
If drier has not been running, energize drier and check
for gradual decrease in temperature at condensate outlet.
Conduction of cold through metal will take about 15
minutes, under no flow condition, to reach 40 to 45 F
(4 to 7 C).
If moisture is detected downstream of the drier,
although drier discharge outlet is cold and trap is working
properly, drier may be operated at too low a pressure or
overloaded by excessive air flow (1-1/2 to 2 HP units
only). Check the compressor tank pressure and percent-
age of operation, The 1 -1/2 HP should not be running
over 75 percent or the 2 HP not over 50 percent.
A burned out refrigeration drier unit can be replaced
with a new unit, or a refrigeration service man may find
and repair leaks and re-charge the unit if there is refrig-
erant loss.
75-7131
Summary of Contents for WP230A-M
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