How do you know if you have a heat pump?

Simply go outside to the outdoor unit and look for a nameplate or sticker on the unit. It will likely be on top or the side. Look for the model number and serial number. Write them down or take a picture with your phone. Make a note of the manufacturer as well. Google the manufacturer name and model number. The results will tell you if it’s a heat pump or an AC unit. You can also check the thermostat for em heat or aux heat settings, which are only for heat pumps. Finally, you can turn on heat and go check your unit to see if it turns on. If it does, it's a heat pump.

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How Do I Know If I Have a Heat Pump?

Split system heat pumps and traditional central AC units look virtually the same. They’re the outdoor condensing unit sitting next to your home. If you just bought a house or condo, you may not know what type of heating and cooling system you have.

The good news is it takes just a small bit of investigative work to find out whether you have a heat pump or an air conditioner sitting outside. Here are 6 things to try. We’d guess you won’t have to try all 6 to get the answer to your question.

#1: Check the owner’s manual

If the home seller was nice, they left you a bunch of owner’s manuals for the dishwasher, washing machine, dryer, and possibly the HVAC system. Look through the manuals, and you may find one for the heat pump, air conditioner, air handler, or furnace. These manuals will tell you about your heating and cooling system.

#2: Look at the product nameplate or sticker

If the weather allows, simply go outside to the outdoor unit and look for a nameplate or sticker on the unit. It will likely be on top or the side. Look for the model number and serial number. Write them down or take a picture with your phone. Make a note of the manufacturer as well.

Some manufacturers list the words heat pump on the nameplate. Look for that too. If you don’t see those words, Google the manufacturer name and model number. The results will tell you if it’s a heat pump or an AC unit.

#3: Check the thermostat

Check the thermostat. If you have a heat pump, there will be a setting for Em Heat, Aux Heat, or both. Only a heat pump thermostat will have these settings.

Aux heat is for when the heat pump needs help heating your home and the thermostat signals the backup heating system to come on. This might be electric heat strips in the air handler, or the backup heat system could be a gas furnace if you have a dual-fuel heat pump system.

Emergency heat comes on only if you manually make the switch. It shuts down the heat pump and the auxiliary heat system becomes the primary system.

#4: Look for the Energy Guide label

Some manufacturers may have put a bright yellow sticker on the inside unit or outside unit that lists the energy ratings. Or the previous homeowner may have left a bright yellow Energy Guide card that came with the unit. If you can find either of those, look for SEER and HSPF ratings.

If HSPF or HSPF2 is listed, you have a heat pump. HSPF stands for heating seasonal performance factor. SEER stands for seasonal energy efficiency ratio. Both an AC unit and heat pump will have a SEER or SEER2 rating, but only a heat pump will have an HSPF or HSPF2 rating listed.

#5: Look for the reversing valve

If you still don’t know if you have a heat pump vs air conditioner, turn the HVAC system off at the thermostat. Go outside, and look into the top of the unit. Wait for the fan to stop moving, and then look down. If you see a brass valve with three fittings on one side, that’s a heat pump reversing valve. This four-way valve is a crucial component in a heat pump. An AC unit will not have this valve.

#6: Switch to heat mode

Finally, if it’s not summertime, turn the thermostat to heat. Go outside. If the outdoor unit kicks on, it’s a heat pump. An AC unit will remain silent. Go back inside and go to where the indoor HVAC unit is located. If you don’t have a heat pump, you probably have a gas furnace, or possibly an electric furnace.

Get to know your HVAC system. If you don’t have the owner’s manuals, Google the model number and download the manual so you can learn about your system and get some troubleshooting tips. The model number and serial number can also tell you how old the unit is, which can help you decide if repair or replacement is a better option if something goes wrong.

Practice heat pump maintenance to maintain comfort

Just like you maintain your car, you need to maintain your heat pump. It works hard to keep you warm in the winter and cool in the summer. By keeping up with air filter maintenance you can prevent a lot of problems. Change standard HVAC air filters every 1-3 months depending on the quality of the filter. If you have an air purification system, you may need to replace the air cleaner insert every 6 months or clean the unit.

Trane heat pumps are premium heating and cooling systems that function best with regular maintenance checks. Schedule professional heat pump maintenance visits for each fall and each spring. Be sure to hire an HVAC company with expertise in heat pumps.

Consider opting into Trane Diagnostics

Take advantage of the peace of mind you get with Trane Diagnostics. Through the Trane Home App and a Trane smart thermostat, you can give your dealer remote monitoring capabilities of your heat pump system. The thermostat sends data in real-time to your dealer, alerting them to maintenance needs or system malfunction, sometimes before you know there’s an issue.

They can run heat pump troubleshooting tests to narrow down or even pinpoint the problem. In some cases, they may be able to fix the problem remotely. In this situation, they would request that you give them one-time dealer remote access (DRA).

If they need to schedule on-site heat pump repair services, the technician will arrive with the knowledge gained from remote access. This results in shorter service calls and ensures the technician has the right replacement parts.

Anne Fonda, Content Writer at Trane Technologies

A Content Writer with Trane Technologies, Anne Fonda researches topics and writes for Trane® and associated residential HVAC brands. She works in collaboration with Trane Technologies subject matter experts, offering easy-to-understand, informative content on complex topics. Her goal is to help consumers make informed decisions on the products and services they need.

She has written for HVAC and other service provider websites for over 16 years. Before transitioning to web content writing, Anne had a 14-year stint as an award-winning journalist. She graduated cum laude from the University of Missouri-Columbia School of Journalism. When she’s not working, Anne enjoys playing word games, reading, gardening, spending time with family, and visiting gardens and museums.

Expert review by Kimberly Sexton, Senior Systems Engineer