Where’s The Reset Button On My Home AC Or Heat Pump System?

If your AC unit has a reset button I hope I can help you find it without too much trouble. First of all it’s quite helpful to have an idea of what an air conditioner or heat pump reset button looks like and what it’s connected to. Below is a reset button on a Rheem heat pump system. The red button is what you’re looking for.

This AC reset below is on the outside of the unit and you won’t have to remove any covers to find that red button. But some resets are on the inside like the Lennox unit above and a little more difficult to find as you can see in that top image. If this button has popped out it will make a slight click when you push in on it.

Shows what the  Rheem heat pump reset button looks like

If your AC unit doesn’t start up when you push the button and you heard or felt a little click when you pushed it, go and double check your thermostat to make sure it’s set for the unit to come on. If you didn’t hear or feel the little click then the reset wasn’t popped off and you have something else wrong.

My AC Reset Button Keeps Popping Out

If your ac unit starts after pushing the button but the reset button keeps popping out it’s time to do something before expensive damage to your unit happens. These reset buttons are set to pop off because of high pressure.

High pressures can be caused by not enough air over the coil which can be caused by no fan or dirty coils. Continually pushing the button to reset your ac condenser can cause serious problems. No fan could be as simple as a capacitor or something more expensive like the condenser motor.

Most articles written about this question do not specify the type of AC units they are talking about because a lot of the terms are the same for window units and full house forced air systems. The reset for a window unit would likely be at the end of the cord. Or, it may have no manual reset.

You may see a similar switch with no reset button. That would be an automatic pressure switch. If their is only one with no button it’s most likely for loss of charge switch. If an air conditioner has a Freon leak this loss of charge switch kills the system to save the compressor.

Pressure switch with no reset button. I’m looking for a better image.

If you can see two of these switches with no reset button, one of them would be for loss of charge and the other a high pressure switch. They reset automatically with the right refrigerant charge, good working fans and clean coils.

If their is no obvious red button on the outside of your unit then look down inside. For safety sake turn off the power before probing around. After you turn off the power, take a small stick or screw driver and spin the fan to get a better look.

Be safe. Can’t say that enough. Sticking stuff in fans isn’t always advisable. Always shut off the power before working on any electrical appliance. Turning off the power is the safe approach. You will still hear a click if the reset button has popped off.

Again this article is about complete whole house forced air systems, not one of those units stuck in a window or on the floor with 4″ vents going out the window.

I think the reason behind not having a reset button is because people like to push them, repeatedly. It should be called a kill switch. They pop open for a reason, usually a bad reason. Push it once, if it pops off again you should call a technician.

To be on the safe side you should call a technician first and let him or her monitor the unit as the reset button is pushed. A good service tech can check a few things before pushing the reset button.

Air Conditioner Reset Button Not Working, What Now?

It’s entirely possible that the reset button never popped off (I almost wrote pooped off, more like pooped out) and the problem is elsewhere. Pushing on the reset and not feeling or hearing a click is indicative of loss of power or a system failure.

The video below demonstrates finding a reset inside an air conditioner and a man pushing the button with a stick. You hear a slight click when he pushes on the reset with his stick. I don’t like sticking sticks inside of units with the power on.

The compressor starts but no fan.

No fan could either mean a bad capacitor or the motor itself. Other possibilities could include bad relays or wires. What this boils down to is that if you push the reset and nothing happens or it starts with no fan, or it starts and the reset pops off again, you need to call a service technician.

I’ve had customers that push their reset button every year and finally they decide somethings wrong and call me only to find out one of their coils is packed with stuff and not enough air is getting through. Even a dirty air filter on a heat pump in the heat mode will pop a reset button. It’s all about air flow, air flow, air flow.

A packed coil is not something you can see right off because of the finned covers and it will lead to an early demise of your system, probably a compressor. Or iced up coils are another result caused by dirty filters and plugged coils. It’s one of the things that can easily be neglected even during a maintenance call.

Summary Of Pressure Switches And Their Purpose

Push it once and hope for the best. If it continues to pop off then get some professional help. The pressure switch has a purpose and that is to protect you against expensive repairs.

You are literally taking a gamble by pushing the switch. It could make the situation worse. Not always, that’s why I call it a gamble.

Chad Peterson

Chad Peterson is a veteran of the HVAC industry since 1977. "I like to explain heating and air conditioning problems in a way the average home owner can understand. "

Recent Posts