How Do I Know If I Have A Heat Pump?
You likely have a heat pump if your outdoor unit runs in winter to produce heat, your thermostat has an "emergency heat'" or "auxiliary heat" setting, and the model/serial plate lists a heat pump designation (e.g., Carrier models prefixed with "25" or "27").
While a heat pump looks identical to a standard air conditioner from the outside, it is uniquely designed to provide both high-efficiency heating and cooling for your home.
Whether you recently moved into a new property or are simply taking a more active role in your home's energy management, identifying your HVAC system is the first step toward a smarter, more sustainable future.
What Is a Heat Pump and How Does It Work?
A heat pump is an innovative, dual-purpose HVAC system that moves heat from one place to another to keep your home comfortable year-round. During the summer, it acts exactly like an air conditioner, extracting heat from inside your home and expelling it outdoors. During the winter, it reverses this process, pulling ambient heat from the outside air and bringing it indoors.
Heat pumps are among the most energy-efficient climate control solutions available. Because they transfer heat instead of burning fossil fuels to create it, they can help reduce energy consumption and help lower energy bills. This intelligent home HVAC solution not only keeps you comfortable but also actively contributes to a healthier planet. Learn more about what is a heat pump and how it works.
5 Ways to Tell If You Have a Heat Pump
If you are asking, "how do I know if I have a heat pump?", you can easily identify your system by checking your thermostat, inspecting your outdoor unit, testing the heating mode, or looking up the manufacturer's model number.
1. Check Your Thermostat Settings
The fastest way to determine if you have a heat pump is to look at your indoor thermostat. Heat pumps rely on a secondary heating source when outdoor temperatures drop dramatically. If your thermostat features settings labeled "EMER" (Emergency Heat) or "AUX" (Auxiliary Heat), you almost certainly have a heat pump. A traditional furnace and air conditioning setup will not have these specific designations.
2. Inspect the Outdoor Unit for a Reversing Valve
Looking inside the outdoor condenser unit can instantly confirm whether you have a heat pump. Look down through the top grill of the outdoor unit (while the power is safely turned off). If you see a brass, multi-pronged component with three tubes on one side and one tube on the other, you are looking at a reversing valve. This intelligent valve is what allows a heat pump to reverse the flow of refrigerant, switching the system from cooling to heating. Standard air conditioners do not have this component.
3. Test the Heating Mode at the Outdoor Unit
You can identify a heat pump by observing the outdoor unit while your indoor thermostat is set to "Heat." Turn your thermostat to heating mode and raise the temperature enough to trigger the system. Walk outside and observe the outdoor condenser. If the fan in the outdoor unit is running and blowing cold air out the top while your house is being heated, you have a heat pump. A traditional furnace operates entirely indoors, meaning the outdoor AC unit would remain completely silent and dormant during the winter.
4. Search the Model Number Online
Locating the manufacturer's model number guarantees an accurate identification of your HVAC system. Walk outside to your condenser unit and locate the metal data plate, usually attached to the side or back of the cabinet. Write down the model number and type it into a search engine. For example, Carrier R-410A refrigerant heat pumps start with "25" and R-454B refrigerant heat pumps start with "27". The manufacturer's product portfolio will immediately indicate whether the unit is a dedicated air conditioner or a versatile heat pump.
5. Check the Energy Guide Label
Examining the yellow Energy Guide label on your outdoor unit can also provide a clear answer. If the label displays both a SEER2 (Seasonal Energy Efficiency Ratio) rating for cooling and an HSPF2 (Heating Seasonal Performance Factor) rating, the unit is a heat pump. Air conditioners only display cooling efficiency metrics. Carrier units typically list the EnergyGuide labels on the upper-right/front area of the outdoor cabinet, where it can be easily seen. Federal labeling rules specify that split-system AC EnergyGuide labels be affixed to the condensing unit. The outdoor unit's silver rating plate is generally on the back of the cabinet, above the service-valve connections. That's different from the yellow EnergyGuide label.
Heat Pump vs. Air Conditioner: What Is the Difference?
The primary difference between a heat pump and an air conditioner is that a heat pump can provide both heating and cooling, while a standard air conditioner provides cooling only.
Jim Snyder, owner of Irish Air in Indianapolis, Indiana, explains why homeowners should know which type of outdoor unit they have.
“It’s important for homeowners to know whether they have a heat pump or a standard air conditioner because the two systems operate differently, especially when it comes to heating,” Snyder said. “An air conditioner only provides cooling, while a heat pump can provide both heating and cooling.”
Both systems use refrigerant to transfer heat and can provide efficient cooling during warm weather. The key difference is that a heat pump has a reversing valve that changes the direction of refrigerant flow. This allows the heat pump to extract heat from outdoor air and move it into the home during the heating season. An air conditioner cannot reverse this process and therefore requires a separate heating system, such as a furnace.
For homeowners looking for a single system that can provide both heating and cooling, a heat pump can offer an efficient all-in-one solution. An air conditioner, on the other hand, is typically paired with a separate furnace or other heating system to provide year-round comfort.
Learn more in our dedicated guide on heat pumps vs air conditioners.
Why Knowing Your HVAC System Matters
Understanding whether you have a heat pump allows you to optimize your home's energy efficiency, schedule appropriate maintenance, and make confident, informed decisions about your climate control.
When you know the exact capabilities of your system, you can operate it at peak performance. For example, knowing you have a heat pump ensures you avoid manually switching to "Emergency Heat" unless absolutely necessary, which saves significant energy.
Furthermore, standard AC units require AC maintenance primarily in the spring, while heat pumps run year-round and benefit from bi-annual heat pump service to remain reliable and sustainable. Empowering yourself with this knowledge ensures your equipment evolves with your needs, keeping you safe, comfortable, and in control. Connect with your local Carrier dealer if you have more questions abut your HVAC system.
Carrier Heat Pump Models
Carrier offers heat pumps across three product lines—Infinity®, Performance™, and Comfort™ Series—with a range of efficiency ratings and technologies. Models within each line can vary in SEER2 and HSPF2 ratings, compressor technology, sound levels, and comfort features, giving homeowners options based on their heating and cooling needs.
| Carrier product line | Efficiency Range* | Compressor technology | Comfort & control features | Designed for |
| Infinity® System | Up to 23 SEER2 / 12.5 HSPF2 | Variable-speed | Advanced temperature and humidity control, Infinity System Control, select models with Greenspeed® Intelligence | Homeowners seeking advanced efficiency, quiet operation and precise comfort |
| Performance™ Series | Up to 19 SEER2 / 10 HSPF2 | Variable-speed, two-stage or single-stage, depending on model | Enhanced comfort and humidity management; select models feature InteliSense™ Technology | Homeowners looking for a balance of efficiency, comfort and features |
| Comfort™ Serie | Up to 16 SEER2 / 8.1 HSPF2 | Single-stage | Standard comfort and humidity management | Homeowners seeking dependable heating and cooling with a focus on value |
*Maximum ratings shown are model-dependent and may vary by system combination, size and installation. Carrier's current lineup includes Infinity models reaching up to 23 SEER2, while Performance models reach up to 18.5 SEER2.
Frequently Asked Questions
No, heat pumps look virtually identical to traditional air conditioners from the outside. Both consist of a large metal cabinet with a fan and condenser coils, which is why checking the thermostat or internal reversing valve is necessary for identification.
Yes, modern heat pumps are engineered to extract heat from the air even in sub-zero temperatures. Cold climate heat pumps are highly reliable, though they may occasionally rely on auxiliary heating strips when temperatures drop significantly below freezing.
A heat pump should be serviced twice a year—once in the spring for cooling and once in the fall for heating. Because it operates continuously throughout the year, it requires more frequent optimization than a standalone air conditioner.
A heat pump has two main components: an outdoor unit placed outside your home and an indoor unit located in a utility room, basement, attic, or closet. The indoor unit connects to your ductwork or distribution system to deliver heated or cooled air throughout your home.
About The Author: Travis Baugh is a Digital Brand Marketing Manager for Carrier, where he develops informative, straightforward content to help homeowners better understand heating, cooling, and indoor air quality. His writing is focused on empowering homeowners to make confident, well-informed choices about their home comfort systems.
About The Expert Reviewer: Zach Dickey is a Product Manager for Residential Heat Pumps at Carrier Corporation, where he helps develop innovative heating and cooling solutions that meet homeowners' evolving comfort needs while aligning with industry trends, energy efficiency standards, and regulatory requirements.