Common HVAC Problem
AC Not Turning On?
You set the thermostat, but nothing happens. No fan, no cooling, no response. This is one of the most common — and most stressful — HVAC problems homeowners face.
Common Causes
Why your AC won't turn on
Before you panic, check these four things. The fix might be simpler — and cheaper — than you think.
Thermostat Batteries
If your thermostat screen is blank or unresponsive, dead batteries are the most likely cause. Many homeowners don't realize their thermostat runs on AA or AAA batteries. Replace them and see if the system kicks back on.
Tripped Breaker
Your AC system typically has two breakers — one for the indoor air handler and one for the outdoor condenser. If either trips, part or all of the system shuts down. Check your electrical panel and reset if needed. If it trips again, call a pro.
Capacitor Failure
The start/run capacitor provides the electrical surge needed to start the compressor and fan motors. When it fails, the system simply won't turn on — or it may try to start and immediately shut off. You might hear a clicking sound.
Contactor Issue
The contactor is the switch that connects power to your outdoor unit when the thermostat calls for cooling. If the contacts are burned, pitted, or stuck, the unit won't receive power even though everything else seems fine.
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