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Advanced Troubleshooting (continued)
Evaporator coil is freezing
Possible Cause
Solution
Charge too low Check for leaks
Add refrigerant
TXV malfunctioning Repair or replace
High pressure switch keeps tripping
Even After Checking for Obstructions and Dirty Filters/Coils
Possible Cause
Solution
Condenser fan not operating Repair or replace
Defective switch Replace
Unit cycles on and off more than 8 times/hr
Possible Cause
Solution
Thermostat malfunctioning Check the thermostat guide for
thermostat information
Low suction pressure Check pressure and adjust superheat
High pitched or loud rubbing noise, clanking or vibration
Possible Cause
Solution
Fans loose or malfunctioning Repair or replace
Excessive compressor vibration Replace
TXV malfunctioning Repair or replace
Replacing the blowers
NOTE: When replacing the fan or motor, replace the fan and motor as a unit.
Do not remove the motor from the impeller wheel.
IMPORTANT
This section is intended for qualified refrigeration service technicians only.
The technician should repeat all the previous troubleshooting steps before taking action on these more
technical solutions.