Thermostat calls for cooling but outdoor unit does not run; indoor blower may run
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Turn off power to the outdoor condenser at the disconnect and breaker before opening any panels.
- Check outdoor breaker/disconnect: Ensure the outdoor unit breaker is ON and the disconnect is fully inserted.
- Verify 24V at contactor: With a call for cooling and power on, a technician can measure 24V across the contactor coil. If no voltage is present, the Y circuit is open between furnace and outdoor unit.
- Inspect Y wiring outdoors: Look for damaged thermostat cable where it enters the outdoor unit. Repair any cuts or rodent damage.
Note: If 24V is present at the contactor but it does not pull in, the contactor coil is likely bad and should be replaced by a technician.
Repair Difficulty
Required Part
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