Few things are more frustrating than a silent air conditioner on a hot day. You expect that cool blast of air when you lower the thermostat—but instead, nothing. Before you panic or assume the worst, take a deep breath.
There are several common reasons your AC might not be turning on, and in many cases, it’s something you can troubleshoot yourself. As HVAC pros, we’re happy to help whenever you need us. But first, here are six air conditioner troubleshooting tips you can try before picking up the phone.
1. Check the Thermostat Settings
It may sound simple, but it’s one of the most common causes of an AC that won’t turn on. Make sure your thermostat is:
- Set to “Cool”
- Set at a temperature lower than the current room temperature
- Powered on (replace batteries if needed)
If your thermostat is blank, unresponsive, or behaving oddly, try changing the batteries or resetting it. A faulty or dead thermostat won’t communicate with your AC system, so this is always a good place to start.
2. Inspect the Circuit Breaker
Your AC system is a high-powered appliance, and it relies on circuit breakers to operate safely. A power surge or overload can trip the breaker and shut down the system completely. What to do:
- Locate your electrical panel
- Check for a tripped breaker labeled “AC” or “HVAC”
- If it’s off or in the middle position, flip it fully off, then back on
If the breaker keeps tripping, that’s a sign of an underlying electrical issue that needs professional attention.
3. Check the Air Filter
A clogged or dirty air filter can restrict airflow so much that it causes the system to overheat and shut down as a safety precaution. Check your filter—if it’s clogged with dust, pet hair, or debris, replace it. We recommend checking your air filter monthly and replacing it every 1 to 3 months depending on usage and household conditions.
4. Look at the Outdoor Disconnect Switch
Most outdoor condenser units have a shut-off switch nearby for safety. Sometimes it can be turned off accidentally during yard work, storms, or maintenance. Find the box mounted on the wall near your outdoor unit. Make sure the disconnect switch is fully in the “On” position.
5. Inspect the Condensate Drain Line
Many modern AC systems have a safety switch that trips if the condensate (drain) line becomes clogged. When this happens, the system will shut down to prevent water damage. Look for a wet area near the indoor unit and/or a blinking light or float switch trigger. If you suspect a clogged drain line, turn off the system and give us a call. We can safely clear the blockage and reset your unit.
6. Listen for Any Sounds or Smells
If your system tries to start but clicks, buzzes, or emits a burning smell, turn it off immediately. These can indicate:
- A failing capacitor
- Electrical issues
- Motor problems
This isn’t a DIY fix—it’s time to call in a licensed HVAC technician to inspect the components and make a safe, professional repair.
Contact Touchstone Heating and Air 24/7 for exceptional customer service! Serving the communities of North Central Florida since 1998.