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REFRIGERATED AIR DRYER INSTRUCTION MANUAL
Ultra Air Refrigerated Dryers
201 Series Instruction Manual
Troubleshooting
Problem: Liquid moisture downstream of dryer
Symptom
Possible cause
Solution
Inlet air temperature
1. Aftercooler failure
1. Clean/repair aftercooler
too high
2. Aftercooler outlet temperature above
2. Check size and capacity against actual conditions
2.
120ºF (49ºC)
Drain not draining
1. Drain valve not opening
1. Check drain electrical connections, make sure timer
condensate
1.
is working properly and if valve is receiving signal,
1.
check valve for clogging
2. Clean valve, replace timer, replace valve if needed
High air flow through dryer
1. Undersized dryer
1. Reduce airflow
2. Replace with larger dryer
High pressure drop across
1. Too much air flowing through dryer
1. Reduce airflow
dryer
2. Air freezing in air-to-refrigerant heat
2. Replace with larger dryer
exchanger
3. Adjust hot gas bypass valve
Refrigerant compressor off
1. Condenser coils clogged or flattened
1. Clean coils and straighten fins
from high refrigerant
2. Fan motor failure
2. Replace fan motor
discharge pressure
3. Aftercooler air discharge blowing on condenser
3. Change aftercooler air flow
4. Inlet compressed air temp. too high
4. Reduce dryer inlet temp. to 120ºF (49ºC) max.
5. Air in refrigerant system
5. Contact certified refrigeration mechanic to repair leak
6. Ambient temp. too high for aircooled condenser
6. Improve ventilation in compressor room
Compressor cuts out; short
1. Refrigeration leak
1. Contact certified refrigeration mechanic to repair leak
cycles on internal overload
2. Refrigeration control valves need adjusting
2. Contact certified refrigeration mechanic to adj. valve
3. Improper ventilation for aircooled condenser
3. Improve ventilation and/or clean condenser.
4. Improper cooling water flow or temp. to
3.
Compressor should restart automatically
4.
condenser
4. Improve and ensure proper water flow and temp.
5. Low voltage
5. Contact electrician for repair.
Compressor will not start
1. Compressor windings opened or shortened
1. Contact certified refrigeration mechanic for repair
2. Compressor burned out
2. Replace compressor
3. Internal mechanical failure
3. Contact certified refrigeration mechanic for repair
High evaporator temperature
1. Refrigeration leak
1. Contact certified refrigeration mechanic to repair leak
refrigerant suction
2. Hot gas bypass valve out of adjustment
2. Adjust hot gas bypass valve by turning clockwise
gauge on “0” PSIG
2.
1/2 turn until suction pressure is between within
2.
appropriate operating range stated on control panel
(R134a reference)
Refrigeration suction temp.
1. Inlet air temp. higher than 120ºF (49ºC)
1. Check aftercooler operation
above operating range
2. Hot gas bypass valve out of adjustment
2. Adjust hot gas bypass valve by turning clockwise
2.
1/2 turn until suction temp. lowers to 28ºF (-2ºC)
3. Refrigerant leak
3. Contact certified refrigeration mechanic to repair leak
Refrigeration discharge
1. Dryer located in a low ambient environment
1. Contact your local distributor
temp. lower than
2. Refrigerant leak
2. Contact certified refrigeration mechanic to repair leak
operating range
Refrigerant discharge
1. Dryer located in a high ambient environment
1. Contact your local distributor
temp above
2. Inlet air temperature too high
2. Reduce temp. to design conditions
operating range
3. Fan motor failure
3. Contact certified refrigeration mechanic for repair
4. Fan motor not running
4. Check fan cycling switches
Problem: Drain valve not discharging moisture
Symptom
Possible cause
Solution
Valve continuously
1. Clogged valve
1. Clean valve
purges compressed air
2. Timer board failure
2. Replace timer board
3. Solenoid valve failure
3. Replace solenoid valve
Valve not opening
1. No power
1. Check power supply and connections
2. Timer board failure
2. Replace timer board
3. Solenoid valve failure
3. Replace solenoid valve
