Pentair t29, Instruction Manual, Page: 15 / 20

© 2015 Pentair Equipment Protection
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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 off. Remove the control box cover and place
both thermostat wires onto one terminal (replace control box cover for safety). This will pass the
switch in the thermostat. Turn the power on. If both blowers and the compressor come on, the
thermostat needs to be replaced.
SYMPTOMS AND POSSIBLE CAUSES:
SYMPTOM POSSIBLE CAUSE
Unit won’t cool
Clogged fins on coil(s)
Dirty filter
Blowers not running
Compressor not running
Compressor runs, but has bad valves
Loss of refrigerant
Compressor tries to start but won’t run
Low line voltage at start. Should be +/-10% rated voltage.
Compressor motor stuck
Bad contactor
Bad overload switch
Bad run/start capacitor
Unit blows breakers
Undersized breaker/fuse or not time delayed
Short in system
Getting water in enclosure
Drain plugged
Drain tube kinked
Enclosure not sealed (allowing humidity in)
Mounting gasket damaged
For additional technical support, contact Pentair Equipment Protection at 800-896-2665.