ductless mini split heat pump installed outside of house with blue exterior blue wall

A primary question new heat pump customers pose is, “What does a heat pump look like?” Though heat pumps have been used for many years, they are less prevalent and familiar than other types of HVAC equipment.

Heat pumps are energy-efficient heating and cooling systems that transfer heat between buildings and the environment. Some heat pumps exchange heat between indoor and outdoor air and others exchange heat between indoor air and the ground. Some heat pumps use ductwork, and others don’t. Two main units are included in most heat pump systems, but the equipment and the appearance differ depending on the heat pump type.

Additionally, the outdoor units of particular heat pumps are so identical to air conditioner units that they can be easily mistaken. Fortunately, homeowners can take specific actions to determine which system they have.

What does a heat pump look like?

There are several types of heat pumps, each with a distinctive appearance. Though each heat pump system has indoor and outdoor units that work together, traditional split systems, ductless mini splits, and ground source heat pumps look different because they operate uniquely.

traditional ducted split heat pump system illustration

Traditional Split System Heat Pump

Traditional split system heat pumps are the most common. These systems use air-source heat pumps to transfer heat between buildings and outside air using an outdoor condensing unit, indoor coil, air handler, and ductwork.

The outdoor unit, a large metal box with fins along the sides and a fan at the top, looks nearly identical to an air conditioning condenser. Heat pumps in cooling mode operate like air conditioners, too. The difference between air conditioners and heat pumps is that heat pump systems also provide heating, and air conditioners cannot.

The air handler houses the indoor coil and uses a blower to push the conditioned air through the ductwork and vents. Air handlers are large metal cabinets resembling furnaces.

Consumers in moderate climates benefit from installing a heat pump vs. a furnace, but some split system heat pumps in cold climates are combined with furnaces. These dual-fuel heat pump systems rely on the heat pump for cooling and most of the heating; the furnace takes over heating when the heat pump loses efficiency in cold weather.

ductless mini split heat pump illustration

Ductless Mini Split Heat Pump

Ductless mini split heat pumps are air-source heat pumps that don’t connect to ductwork. The indoor and outdoor units of ductless mini-split systems look different from traditional ducted heat pumps. The outdoor units are significantly smaller, with fans on the sides rather than the tops, and they typically sit on wall brackets.

The indoor units are typically wall-mounted, rectangular boxes but they can also be ceiling-mounted, floor-mounted, or ceiling suspended. Mini-split systems can include a single indoor unit in one room or several indoor units, each installed in separate rooms.

Ground Source Heat Pump

Ground source heat pumps, a form of geothermal heating and cooling, work differently than air source heat pumps and include different components. The outdoor section consists of underground pipe networks to exchange ground heat with indoor heat. Ground source systems require substantial yard space. Pipes can be laid horizontally underground or vertically in boreholes. The outdoor systems connect to indoor systems.

Where is the heat pump located?

Air source heat pumps have units inside and outside the house. The outdoor unit can be easily located by walking around the home’s perimeter. A ducted system’s indoor unit is concealed in the air handler, whereas a ductless system has one or more indoor units installed in the house’s rooms.

Indoor Unit

A ducted system’s indoor unit installs inside the heat pump air handler or furnace. An air handler is a large metal cabinet resembling a furnace. Air handlers use blowers to push cooled or heated air through the home’s ductwork. Air handlers and furnaces are typically installed in well-ventilated, remote areas of houses, such as utility rooms, basements, and attics.

The indoor units of ductless systems are easier to spot because they are installed in the living spaces and mounted on walls or ceilings. Visibility is one drawback of ductless systems.

Outdoor Unit

The outdoor units of ducted and ductless systems are typically installed near an exterior wall in a side yard or backyard. A ducted system’s unit sits on the ground or brackets near ground level. A ductless system’s unit is typically mounted on wall brackets and is much smaller than ducted units.

How do I know I have a heat pump or an air conditioner?

How do I know if I have a heat pump? The outdoor units of heat pumps and air conditioners are nearly identical, but there are several ways to tell them apart:

  • Check the labels

  • Check for the emergency heat setting

  • Look for the reversing valve

  • Adjust the thermostat settings

Check the labels: Find the brand name and model number on the outdoor unit’s label and type them into an Internet search engine.

Check for the emergency heat setting: Look for an emergency heat or EM heat setting on the thermostat. You definitely have a heat pump if there’s an emergency heat setting. But not all heat pump systems include backup heating, so the absence of EM heat does not guarantee that you don’t have a heat pump.

Look for the reversing valve: Look through the outdoor unit’s top grille for the reversing valve, which allows heat pumps to cool and heat homes. The valve resembles a horizontal brass pipe attached to four copper lines. If it has a reversing valve, it’s a heat pump. Access panels obscure some reversing valves, so the inability to locate it doesn’t guarantee that it’s not a heat pump.

Adjust thermostat settings: Turn the thermostat’s heat on, then go outside to the condenser unit. You have a heat pump if the condenser runs when the heat is on.

Conclusion

There is no simple explanation for what an electric heat pump looks like because of the several types of heat pumps. Air source, ground source, ducted, and ductless heat pump systems operate differently and use unique components. But all of these systems have one fact in common–they have indoor and outdoor units.

Traditional split systems are ducted air source heat pumps. These systems have large, metal outdoor units that resemble air conditioner condensers installed along exterior walls near ground level. The indoor units are housed in air handlers.

Ductless mini-split systems are another type of air source heat pump. These systems have small, metal outdoor units with fans on the sides, typically bracketed to exterior walls. The indoor units of mini split systems are typically mounted on the rooms’ walls but might be floor or ceiling mounted.

Ground source systems are vastly different from air source systems. The outdoor components, consisting of pipe networks, are buried underground and connected to the indoor units to exchange ground heat with indoor heat.

There are four steps you can take to determine if you have a heat pump:

  • Search the brand and model number on the outdoor unit’s label

  • Check if the thermostat has an emergency heat setting

  • Look for a reversing valve in the outdoor unit

  • Check if the outdoor unit runs when the heat is on


Frequently Asked Questions

Can a heat pump be located in an attic?

Heat pump air handlers can be located in attics, but some disadvantages include inaccessibility and susceptibility to rodent damage, poor air quality, and inefficient performance.

Can a heat pump be located under a deck?

Heat pumps should not be installed under decks. Heat pumps require unrestricted airflow and two feet of clearance on all sides. Summertime temperatures under decks can be significantly higher than the outdoor air, reducing heat pump efficiency and lifespan.

Where is my geothermal heat pump located?

Geothermal heat pump systems have two parts. The indoor component is typically located in the same space a furnace or boiler would be installed. The outdoor component is buried in the yard below the frost line.

Leave a comment

All comments are moderated before being published