This is one of the most common summer calls: the thermostat says cooling, the system sounds like it is running, but the home does not cool down.
The cause can be simple, like a dirty filter or a tripped breaker. It can also be a failed capacitor, refrigerant leak, frozen coil, or compressor issue.
Check these first
What you can safely check before calling
Confirm the thermostat
Set it to Cool and lower the target temperature by a few degrees. Make sure a schedule or hold setting is not fighting you.
Check the filter and airflow
Replace a dirty filter and feel airflow at several vents. Weak airflow usually points toward blower, filter, coil, or duct restriction.
Look outside
The outdoor fan should be running during a cooling call. If the indoor blower runs but the outdoor unit is silent, it may be electrical.
Check breakers once
If a breaker is tripped, reset it one time. If it trips again, leave it off and call for service.
Likely repair causes
What usually needs a technician
Failed capacitor or contactor
These parts help start and power the outdoor unit. They are common same-day repairs.
Low refrigerant charge
Low charge usually means a leak. It can make the AC run nonstop while barely cooling.
Frozen indoor coil
Ice blocks airflow and cooling. The coil must thaw before pressure readings are accurate.
Dirty condenser coil
Cottonwood, leaves, and debris can stop the outdoor unit from dumping heat.
Call if you see this
When to stop troubleshooting and schedule service
- The outdoor unit is not running during a cooling call.
- The vents blow warm or room-temperature air.
- The AC runs for hours and cannot lower the temperature.
- A breaker trips more than once.
Next step
