HVAC Problem Diagnosis · Phoenix Metro
AC Won't Turn On
An AC that will not start can be caused by a tripped breaker, thermostat issue, failed capacitor, blown low-voltage fuse, float switch, contactor, or a larger electrical problem. Sapper HVAC diagnoses the system before replacing parts.
Request HVAC Diagnosis
Tell us what the system is doing and where you are located.
Possible causes
- Tripped breaker or disconnect issue
- Failed capacitor or contactor
- Thermostat or low-voltage control problem
- Condensate float switch shutoff
- Motor or compressor electrical failure
Safe checks before calling
- Confirm the thermostat is set to COOL and below room temperature
- Check whether the thermostat display has power
- Check the HVAC breaker once; do not repeatedly reset a breaker that trips again
- Replace a visibly dirty return filter if airflow is severely restricted
The symptom is not always the failed part
Many HVAC failures create the same symptoms. A failed capacitor can look like a compressor problem. Low refrigerant can look like an airflow problem. A float switch can make a healthy system appear completely dead. Sapper HVAC starts with diagnosis so the repair is based on what actually failed.
