Gardner Denver RHS20 SCFM Manual page 23

SYMPTOM
Excessive pressure drop within the dryer.
DewPoint too low.
LED of the Air Dry Controller is always on.
Excessive pressure drop within the dryer.
7.2 DISMANTLING OF THE DRYER
If the dryer is to be dismantled, it has to be split into uniform groups of materials.
The refrigerant contains droplets of lubrication oil released by the refrigerating compressor. Do not dispose this
fluid in the environment.
Is has to be discharged from the dryer with a suitable device and then delivered to a collection center where it will
be recycled.
POSSIBLE CAUSE - SUGGESTED ACTION
The dew point is too low - the condensate is frost and blocks the air -see
the specific section.
Check for restriction in the flexible connection hoses.
Verify the electric wiring of the Air Dry Controller.
Verify the wiring of the hot gas by pass solenoid valve.
The coil of the hot gas by-pass solenoid valve burned out - replace.
The probe of the Air Dry Controller does not properly detect the
temperature of the evaporator - push the probe until it reaches the
bottom of the measurement well.
The set point of the Air Dry Controller is very low - see paragraph SET-
UP of the Air Dry Controller.
Air Dryer Controller doesn't work - replace.
The hot gas solenoid valve is blocked - contact a refrigerating systems
engineer.
Verify the electric wiring of the probe of the Air Dry Controller.
The first and the last led of the display of Air Dry Controller blink
simultaneously, the probe doesn't work - replace.
Air Dryer Controller doesn't work - replace.
The dew point is too low - the condensate is frost and blocks the air -
see the specific section.
5 micron filters is clogged - replace the cartridges.
Check for throttling the flexible connection hoses.
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