Instruction manual
© 2012 Pentair Technical Products
87976469
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TROUBLE SHOOTING
Basic Air Conditioning Trouble Shooting Check List
1. Check manufacturer’s nameplate located on the unit for correct power supply.
2. Turn on power to the unit. The evaporator (Enclosure or “COLD” air) blower should come on. Is there
airow?
YES, proceed to step 3.
NO, possible problem:
• Open motor winding
• Stuck blower motor
• Obstructed blades
Repair or Replace
defective part
3. Check thermostat setting and adjust thermostat to the lowest setting. This should turn on the
condenser blower and compressor. Did condenser blower and compressor come on when the
thermostat was turned on?
YES, proceed to step 4.
NO, possible problem:
• Defective thermostat Replace Part
4. Are both blowers and the compressor running? If not the unit will not cool properly.
5. Check condenser (Ambient or “HOT” air) blower for airow. Is there airow?
YES, proceed to step 6.
NO, possible problem:
• Defective thermostat
• Open motor winding
• Stuck blower motor
• Obstructed wheels/blades
Repair or Replace
defective part
6. Carefully check the compressor for operation - motor should cause slight vibration, and the outer case
of the compressor should be warm. Is the compressor showing signs of this?
YES, wait 5 minutes, then proceed to step 7.
NO, possible problem:
• Defective thermostat
• Defective capacitor
• Defective overload
• Defective relay
Repair or Replace
defective part
7. Make sure the coils are clean. Then check evaporator “air in” and “air out” temperatures. If the
temperatures are the same:
• Possible loss of refrigerant
• Possible bad valves in the compressor
Repair or Replace
defective part
8. To check for a bad thermostat, turn power to the unit o. Remove the control box cover and place
both thermostat wires onto one terminal (replace control box cover for safety). This will activate the
switch in the thermostat. Turn the power on and if both blowers and the compressor come on, the
thermostat needs to be replaced.