How To Reset An Air Conditioning Unit? [5 Methods Included]

While an HVAC professional can always solve the problem, you can sometimes get your broken air conditioner to work again by resetting it. But how to reset an air conditioning unit?

Different air conditioner types and brands may use different methods. In this post, I’ve summarized five common ways to reset an ac so you can pick the one that works best for you.

Why does your air conditioner need a reset?

There are numerous electrical components in air conditioning units. Many require a reset to function properly, particularly after a power outage, a power surge, or a sudden disconnect.

This is because the ac has two circuit breakers to prevent fires and other hazards. When the power is restored after an outage or disconnect, the sudden increase in voltage will trip the circuit breaker, and some ac components will begin to work incorrectly.

In this case, a reset can give these components a break and allow them to resume normal operation.

1. Reset your AC with a reset button 

Some air conditioners include a reset button for resetting the machine.

Many people are unaware of the location of the air conditioning unit’s reset button. In most cases, it is located near the service panel or on the bottom edge of the outdoor unit.

If you have a portable or window air conditioner, the reset button is usually located on the cord.

The reset button is easily identified by its visible red color. The location information should be available in the manual.

What to do?

Release the reset button after three to five seconds. If it doesn’t work, unplug the unit, wait 30 seconds, then plug it back in and press the reset button again.

2. Reset your AC with an isolator switch

Another safety feature of an air conditioner is the isolator switch. It is linked to the main power supply and is located near the condenser. Your air conditioner will be reset by turning it on and off.

The isolator switch is white, but because it is relatively large, it is easy to see. It has a lever on a V-shaped socket, and you turn it off by pushing down on the lever.

What do to?

Turn off your air conditioner and then look for the isolator switch. Turn the switch off and wait for at least three minutes before turning it on. Then you should wait about five minutes before turning on your ac unit.

This video below will guide you how to do it exactly.

3. Reset your AC with a circuit breaker

This is another method for turning off the power and resetting your ac. The ac circuit breaker is usually found in a breaker box, which contains several circuit breakers.

The metal box is mounted on the wall of your basement, crawlspace, garage, or home’s exterior.

What to do?

Turn off the ac at the thermostat and then look for the location of the breaker box. Don’t turn off all the circuit breakers in the box! There is a circuit breaker for ac, and you only need to switch it off. 

Turn it on after at least one minute, and turn on your ac at the thermostat after half an hour.

4. Reset your AC by unplugging the cord

Some ac models do not necessitate a complicated resetting procedure. They can be reset automatically once power is restored.

What to do?

Remove the air conditioner’s power cord from the outlet. Wait one minute before reconnecting the ac.

5. Reset your AC with a thermostat

In rare cases, your air conditioner fails to function properly because it does not receive the correct signal from the thermostat. That is, you can reset your air conditioner by resetting your thermostat.

What to do?

Locate the thermostat’s “reset button,” hold it down for about five seconds, and then release it. If that doesn’t work, try replacing the batteries.

What to do if all the resetting methods don’t work?

If you’ve tried everything to reset your ac and it’s still not working, you can start looking for the source of the problem.

For example, if your air conditioner isn’t cooling, check to see if the filter is too dirty, the vent is blocked, or the compressor is damaged.

If your air conditioner keeps turning on and off, check to see if the refrigerant is leaking, the evaporator coil is frozen, or the condenser coil is filthy.

Some issues, such as cleaning the air filter or compressor coils, can be resolved on your own, but others may necessitate the assistance of a certified HVAC expert. Note that it is not permitted and can be dangerous to attempt to recharge your ac.

If the compressor is damaged, you may be better off buying a new unit because the compressor is costly to replace or repair.


Sometimes, an air conditioning unit can fail for no specific reason, and you can recover it via a reset. 

You can reset your ac unit by making use of a reset button, a circuit breaker, or an isolator switch. Resetting the thermostat or unplugging the unit can also work.

However, a reset can’t solve all the problems. You need to look for other solutions if something in your ac does go wrong.

About The Author

Avatar photo

Liz Yang is the founder of Airsmartly. She has been working at home for a few years and realizes that the performance of the HVAC system plays such an important role in our life. She has tested dozens of products in person, like humidifiers, air purifiers, dehumidifiers, and ACs, and wants to share tips about using or troubleshooting these products with you. Her uncle is an HVAC expert with over 30 years of experience in the field, and often offers assistance when she is unsure how to handle a situation. He is also in charge of reviewing the articles on this site.

Leave a Comment