101
TROUBLESHOOTING
Troubleshooting AC - No Cool
No
Yes
No Cool
No
No
Yes
No
Compressor
Running
Repair or Replace Wiring
Replace Capacitor
Check for Stuck Compressor
Check Refrigerant Charge and
Amp Draw
Replace Compressor
Yes
Replace Contactor
Yes
No
Repair or Replace Metering
Device
Metering Device
Working Properly
No
Check Thermostat and
Thermostat Wires
Check control board no voltage
out of board replace board
No
Replace Motor
Contactor
Open
Wiring to
Compressor
OK
Yes
Run Capacitor
Good
Compressor
Overload
Open
Compressor
Windings
Open
Replace Compressor
Compressor
Warm to
Touch
Did Compressor
Restart After
Allowing to Cool
Yes
Replace Compressor
230 Volts to
Unit
Check Breakers or Fuses
Yes
230 Volts to
Transformer
Check Wiring from Contractor to
Transformer
Yes
24 Volts from
Transformer
Yes
24 Volts on Y
from
Thermostat
Yes
24 Volts to
Contactor Coil
Yes
No
No
No
No
No
No
No
No
No
Yes
Yes
Yes
Check Pressure Switches and
Wiring
Check Thermostat and
Thermostat Wiring
Replace Transformer
Compressor
Pumping
Yes
Replace Compressor
Yes
Indoor Blower
Runnng
No
No
Voltage to
Indoor Motor
Yes
24 Volts on G
from
Thermostat
Yes
Check wires and voltage at
control board
2nd Stage
Operating
No
Check voltage
to 2nd stage
solenoid
No
Yes
Coil shows
infinite, zero
or ground
Yes
No
Check compressor windings
Check compressor windings and
if faulty, replae compressor
Check
resistance of the
unloader coil
Yes
Unit operating properly
Solenoid coil
has continuity
Replace compressor
Yes
No
AC - NO COOL
