Why Won’t Your AC Turn On? The Thermostat Might Not Be the Problem

Nothing feels worse than switching on your AC on a hot day, only to realize… it won’t turn on. While your first instinct might be to blame the thermostat, it might not be the culprit. 

There are several other reasons why your AC refuses to start, and some might be easier to fix than you think. Let’s check out some common causes and what you can do about them.

1. Check Your Circuit Breaker

Your AC system requires a lot of power, and sometimes, that extra demand can trip your circuit breaker. If your AC isn’t turning on, locate your home’s electrical panel and check if the breaker for your AC unit has flipped to the “off” position. If it has, flip it back on. However, if it keeps tripping, this could indicate a deeper electrical issue that requires professional attention.

2. Examine the Drain Pan and Float Switch

Your AC unit removes moisture from the air, which drains into a pan. If the pan fills up due to a clogged drain line, the float switch may trigger and shut off your system to prevent water damage. Check the drain pan for standing water. If it’s full, you may need to unclog the drain line or call a professional to clear it.

3. Look at the Power Switch

It sounds simple, but sometimes, the power switch near your indoor unit may have been accidentally turned off. This switch, usually located near the furnace or air handler, resembles a regular light switch. If it’s off, turn it back on and see if your AC starts running.

4. Check for a Blown Fuse

Your AC system has fuses that protect it from power surges. If a fuse blows, your system won’t start. If you suspect a blown fuse, it’s best to have an HVAC technician test and replace it safely.

5. Don’t Ignore the Capacitor

The capacitor helps start the AC’s compressor and fan motors. Over time, capacitors can wear out, preventing your system from turning on. If you hear a faint clicking sound but the unit won’t start, a faulty capacitor could be the issue. A technician can replace it quickly.

When is the Right Time To Contact a Professional?

If you’ve checked these common issues and your AC still won’t turn on, it’s time to call in the experts. Electrical problems, refrigerant leaks, and compressor failures require professional diagnosis and repair.