The quickest way to identify a heat pump

Look outside your home for a single outdoor unit that looks like an air conditioner box. If you have one outdoor unit and your system heats in winter and cools in summer, it is almost certainly a heat pump. A traditional system has two separate units — one for heating (a furnace) and one for cooling (an air conditioner) — or just one unit if you only cool.

The outdoor unit is the easiest place to start because it is visible and the label tells you what you own. Walk around to the side or back of your house where the HVAC equipment sits. If there is a single metal box about the size of a large trash can or air conditioner unit, read the nameplate on it. The manufacturer and model number are printed there.

Heat pump manufacturers include Carrier, Trane, Lennox, Rheem, Goodman, and Daikin. The word "heat pump" usually appears on the label itself. If you cannot read the label clearly, take a photo and search the model number online — the product sheet will confirm what type of system it is.

Key Takeaways

  • A heat pump has one outdoor unit that both heats and cools, while a traditional system has separate units for heating and cooling or only cools.
  • The manufacturer nameplate on the outdoor unit will say "heat pump" if that is what you own.
  • If you have a furnace indoors and an air conditioner outside, you have a traditional split system, not a heat pump.
  • Some heat pumps are paired with a backup furnace for very cold weather, but the outdoor unit label will still identify it as a heat pump.
  • Checking your thermostat settings and looking at your utility bills can confirm what you have if the outdoor unit label is unclear.

Check your thermostat for heat pump clues

Your thermostat display often shows what type of heating system you have. Look at the mode buttons or settings on your thermostat. If you see a button or setting labeled "Heat Pump" or "HP," you own a heat pump. Some thermostats also show "Emergency Heat" or "Aux Heat" — this is a backup heating mode that heat pumps use when outdoor temperatures drop too low.

Modern programmable and smart thermostats (like Nest, Ecobee, or Honeywell Home) usually display the system type during setup or in the settings menu. If you have an older manual thermostat with a dial, look for a switch labeled "Heat," "Cool," "Auto," or "Off." Heat pumps have an "Auto" mode that automatically switches between heating and cooling. A traditional furnace-plus-air-conditioner system may not have this option, or it works differently.

If you are unsure how to read your thermostat, take a photo of the front and the label on the back. The label often lists the model number and compatible system types. You can also search that model number to find the manual online.

Look at your indoor equipment

Walk to your furnace or air handler — the large metal box usually in a basement, attic, or utility closet. If you see a furnace (a large unit with a burner, gas line, or electric heating element), you have a traditional heating system, not a heat pump. Furnaces burn fuel or use electric resistance to create heat.

If instead you see an air handler — a smaller metal box with a blower fan and refrigerant lines running to it — you likely have a heat pump. An air handler moves heated or cooled air through your ducts but does not create heat itself. The heat comes from the outdoor unit.

Some homes have both: a heat pump paired with a backup furnace for extreme cold. In this case, the outdoor unit is still a heat pump, and the furnace kicks in only when the heat pump cannot keep up. The nameplate on the outdoor unit will tell you it is a heat pump regardless of whether a furnace is also present.

Trace the refrigerant lines

Refrigerant lines are the copper or aluminum pipes that run between your indoor and outdoor units. Heat pumps always have two refrigerant lines — one carries cold refrigerant into the house, and one carries warm refrigerant back out. These lines are usually insulated with foam or rubber tubing and run along the outside of your home to the outdoor unit.

If you see two refrigerant lines running from an outdoor unit to an indoor unit, that is a strong sign of a heat pump. A traditional air conditioner also has two lines, but it will be paired with a furnace indoors, not an air handler. If you see refrigerant lines but no furnace inside, you have a heat pump.

Do not touch the refrigerant lines — they are under pressure and extremely cold. Just look at them to confirm they exist and count how many there are. If you cannot see the lines clearly, they may be hidden in the wall or routed through the attic.

Check your utility bills and heating patterns

Heat pump owners usually see a noticeable difference in their heating bills compared to furnace owners. Heat pumps use electricity to move heat rather than burn fuel, so your electric bill may be higher in winter if you have a heat pump. If you switched from a furnace to a heat pump, your gas bill would drop to nearly zero in winter.

Think about how your system heats. If your home warms up gradually over several hours when you turn up the thermostat in winter, you likely have a heat pump. Heat pumps move heat slowly and steadily. If your home warms up quickly within minutes, you probably have a furnace or electric resistance heating.

Look at your past 12 months of utility bills. If your electric usage spikes in winter and your gas usage stays low or zero, you have a heat pump. If your gas bill spikes in winter and your electric bill stays relatively flat, you have a gas furnace.

Ask your HVAC contractor or previous owner

If you bought your home recently, the home inspection report or closing documents may list your HVAC system type. Real estate disclosures often include the age and type of heating and cooling equipment. Check any paperwork you received at closing.

If you rent, your landlord or property manager can tell you what system is installed. They have maintenance records and know whether the outdoor unit is a heat pump or air conditioner.

You can also call a local HVAC contractor and describe your outdoor unit or give them the model number. They can identify your system over the phone in minutes. Many contractors offer free phone consultations, and you do not need to schedule a service visit just to find out what you have.

Common mistakes when identifying a heat pump

Do not assume that a single outdoor unit is always a heat pump. Some homes have a single air conditioner unit for cooling only, with a furnace inside for heating. The difference is whether the system heats in winter. If you only have cooling and use a furnace or electric baseboard heaters for warmth, you do not have a heat pump.

Do not confuse a heat pump with a ductless mini-split system. Mini-splits also have one outdoor unit and one or more small indoor units mounted on walls. They are a type of heat pump, but they look different because the indoor units are small wall-mounted boxes instead of a central air handler. If your indoor units are small boxes on the wall rather than a large central unit in a closet or basement, you have a mini-split heat pump.

Do not rely only on the age of your home. Older homes can have heat pumps, and newer homes can still have furnaces. The equipment itself, not the house age, determines what you have.

Frequently Asked Questions

Can a heat pump have a furnace too?

Yes. Many homes pair a heat pump with a backup furnace for very cold weather. The heat pump handles most of the heating, and the furnace activates only when outdoor temperatures drop below the heat pump's efficient range — usually around 35 to 40 degrees Fahrenheit. The outdoor unit will still be labeled as a heat pump.

What if I cannot find the outdoor unit?

Some outdoor units are hidden behind a fence, in a side yard, or on a roof. Walk around your entire home perimeter and look for a metal box about the size of an air conditioner. If your home is very small or you have only window units, you may not have a central HVAC system at all. In that case, you have room air conditioners or space heaters, not a heat pump.

Does the nameplate say "heat pump" or something else?

The label should say "heat pump" clearly, but older units may say "reverse cycle air conditioner" or "heating and cooling unit." These are heat pumps under different names. If the label says only "air conditioner" with no mention of heating, it is not a heat pump — it cools only.

What if my thermostat does not show the system type?

Look at the model number on the thermostat itself and search it online. The product manual will list compatible system types. You can also photograph the outdoor unit nameplate and search that model number — the manufacturer's product sheet will confirm whether it is a heat pump.

Can I tell by looking at my electric meter?

Not directly. Heat pumps use more electricity than air conditioners alone, but your meter does not tell you what type of system you have. Compare your winter and summer electric bills instead. If winter bills are significantly higher than summer bills, you likely have a heat pump or electric heating.