High Inlet Temperature Refrigerated Air Dryer
21
Problem
Probable Cause
Remedy
Water downstream and
dryer system not working
properly or not working
(Cont).
Refrigeration compressor
short cycles and cannot
maintain suction pressure,
dryer undersized.
Check airflow (cfm) and dryer capacity. Reduce
airflow through dryer or replace with a larger
rated cfm dryer.
Shorted fan motor
winding.
Check fan motor with ohmmeter and refer to
motor specifications for correct value and check
wiring schematic to ensure proper wiring of fan
motor. Replace motor if required.
Fan motor overload
cutting out or unit short
cycling.
Check circuitry against electrical schematic
(wiring diagram). Check for high refrigerant
pressure or for high ambient temperature.
Defective overload
protectors (fuses or
breakers).
Check overload protectors and replace if
necessary.
Low voltage or 3-phase
imbalance.
Check incoming power supply, voltage must be
within 8-12% of rating on data plate.
Low water flow or
pressure to water-cooled
condenser.
Check water flow and/or pressure and adjust
according to specifications.
Defective fan control
cycling switch.
Replace fan control cycling switch.
Low air pressure
downstream or high
pressure drop across
the dryer system.
Optional pre-filter element
dirty or plugged.
Replace filter element.
Suction pressure below
set point which causes
freezing in the dryer heat
exchanger.
If expansion valve is out of adjustment, contact
an authorized service technician.
Notice: To confirm
freeze-up, shut system
off for 20 min and allow
to thaw. Air pressure in
line should come back
to normal pressure.
Suction pressure below
set point which causes
freezing in the dryer heat
exchanger.
Refrigeration circuit low on refrigerant, locate
leak in refrigeration circuit, repair and recharge
according to specifications.
Incorrect sizing or restriction
in compressed air line
piping.
Check compressed air piping for restrictions.
Check piping size to verify if it has the capacity
to handle the rated scfm at present working
pressure of compressed air system.
Summary of Contents for DHT-100
Page 12: ...12 Typical Installation Aircel DHT Series Models 20 125 Typical Installation...
Page 33: ...33 Service Notes Date Service Performed Notes High Inlet Temperature Refrigerated Air Dryer...
Page 34: ...34 Service Notes continued Date Service Performed Notes Aircel DHT Series Models 20 125...
