Heat pumps are usually outside your home, mounted on the ground or wall
The outdoor unit of your heat pump sits in a metal cabinet, typically the size of a large air conditioner box. It looks like a rectangular or square enclosure, usually 2 to 3 feet tall and wide, made of aluminum or steel. Most homeowners find theirs along the side or back of the house, on the ground or mounted 1 to 2 feet up a wall. Some are tucked into a corner, under a deck overhang, or in a side yard where it has clearance on all sides.
If your home has a split-system heat pump—the most common type—there is also an indoor unit. This sits inside your house, usually in a closet, basement, attic, or utility room. The indoor unit is smaller and quieter than the outdoor one, and it connects to the outdoor unit by refrigerant lines that run through your wall or foundation.
A few homes have packaged heat pumps, where everything is in one unit. These sit entirely outside, usually on the roof or on a concrete pad at ground level. If you have a packaged system, that single outdoor box is your entire heat pump.
Key Takeaways
- The outdoor unit of a split-system heat pump sits in a metal cabinet on the ground or mounted on a wall, usually along the side or back of your house.
- The indoor unit of a split-system is smaller and quieter, located in a basement, attic, closet, or utility room inside your home.
- Packaged heat pumps have only one unit, mounted on the roof or on a ground pad outside.
- The outdoor unit needs at least 12 inches of clearance on all sides to run efficiently and avoid ice buildup or airflow problems.
- If you cannot find your heat pump, check your home's HVAC paperwork, ask your installer, or look for the refrigerant lines running into your house.
Finding the outdoor unit in your yard
Start by walking around the outside of your home and looking for a metal box about the size of a window air conditioner unit, but taller. The outdoor unit is usually painted gray, tan, or white. Listen for a humming or buzzing sound—the compressor inside runs when the system is heating or cooling. If your heat pump is running, you will hear it from several feet away.
Check the most common spots first: the side of the house nearest the main living area, the back corner away from the street, or along the foundation. Some units sit on a concrete pad; others are bolted to a metal frame mounted on the wall. If you have a deck or patio, the unit might be tucked underneath or just beyond it.
Look for the refrigerant lines—two copper or aluminum tubes that run from the outdoor unit into your house through the wall or foundation. These lines are usually wrapped in foam insulation and are about the thickness of your thumb. Following them will lead you straight to the outdoor unit if you are unsure which box is yours.
Locating the indoor unit inside your home
The indoor unit is much smaller than the outdoor one—usually a rectangular box 12 to 24 inches wide and 6 to 12 inches deep. It is often white or beige and may have a metal grille on the front. This unit is quieter than the outdoor one and does not need outdoor clearance, so it can fit in tight spaces.
Check your basement first, especially near the furnace or water heater. If you do not have a basement, look in a utility closet on the first floor, in an attic, or in a garage. Some homes have the indoor unit mounted on a wall inside a bedroom or hallway closet. The refrigerant lines running from outside will lead you to it—follow them through your walls and you will find where the indoor unit connects.
If your home has ductwork, the indoor unit is usually positioned near the main duct trunk so it can distribute heated or cooled air throughout the house. If you have a ductless system (also called a mini-split), the indoor unit is a wall-mounted or ceiling-mounted box in the room you want to heat or cool, and there may be several of them in different rooms.
What to check once you find your heat pump
Once you locate the outdoor unit, make sure it has at least 12 inches of clear space on all sides. Leaves, snow, ice, or debris blocking the unit will reduce its efficiency and can damage the compressor. Clear away any plants, mulch piles, or stored items that are closer than a foot away.
Check that the unit is sitting level on its pad or mounting bracket. If it is tilted or leaning, water can pool inside and cause rust or electrical problems. A slightly uneven pad is normal, but if the unit is visibly crooked, contact your installer.
Look at the refrigerant lines where they enter your house. They should be wrapped in foam insulation and not cracked or peeling. If the insulation is damaged, cold air escapes and your system works harder than it should. Small gaps are normal, but large bare sections should be re-wrapped.
Finding your heat pump if you just moved in
If you inherited a heat pump with your home and do not know where it is, start with your home inspection report or closing documents. These often include a list of major systems and their locations. If you have those papers, they may describe the heat pump's position or even include photos.
Ask your neighbors—they may have seen the installation or know where similar units are placed in the neighborhood. Call the previous owner if you have their contact information; they can tell you exactly where to look and may have the installer's name and phone number.
Check your electrical panel or furnace closet for a label or sticker with the heat pump's model number and the installer's name. Many installers leave contact information on the unit itself or on a nearby wall. If you find the installer's name, you can call them to ask where the unit is located and get maintenance information.
Understanding outdoor unit placement and why it matters
Heat pump outdoor units are placed where they have good airflow and are away from direct sun exposure when possible. Too much sun can make the unit work harder in summer, and too much shade can allow ice to build up in winter. Most installers aim for a spot that gets morning sun but afternoon shade.
The unit also needs to be away from noise-sensitive areas—bedrooms, patios, or neighbors' windows—because it does make noise when running. A unit on the back corner of your house is usually quieter than one on the front or side near where you spend time outdoors.
If your outdoor unit is in an unusual spot—on the roof, in a basement window well, or mounted very high on the wall—that is fine as long as it has clearance and is find. Some homes have space constraints that force creative placement. What matters is that the unit can pull in fresh air and push out warm or cool air without obstruction.
Frequently Asked Questions
Can a heat pump be inside the house only?
No, a heat pump must have an outdoor unit to exchange heat with the outside air. The outdoor unit is the core of the system. You may have an indoor unit as well (in a split system), but you cannot run a heat pump with only an indoor component. If you see only an indoor box, it is likely an air handler paired with the outdoor heat pump unit.
What if I cannot find an outdoor unit anywhere on my property?
Check whether your home actually has a heat pump or a different heating system like a furnace or boiler. Look at your thermostat—if it says "heat pump" or "HP" in the mode options, you have one. If you still cannot find it, the unit may be on a neighbor's property line (in rare cases), in a shared utility area (in apartments or condos), or on the roof where it is not visible from the ground. Call your HVAC company or the previous owner to confirm.
Is it normal for the outdoor unit to be noisy?
Yes, some noise is normal—a humming or buzzing sound when the compressor runs is typical. A loud rattling, grinding, or squealing noise is not normal and means something may be loose or broken inside. If you hear unusual sounds, turn off the system and call your installer or an HVAC technician to check it.
How often should I clean around the outdoor unit?
Check the area around your outdoor unit once a month during fall and winter to clear leaves, snow, and ice. In summer, make sure grass and weeds are not growing right up against it. You do not need to clean the unit itself—that should be done by a technician during annual maintenance—but keeping the space around it clear helps the system run efficiently.
Can I move my heat pump to a different location?
Moving the outdoor unit is possible but expensive because the refrigerant lines, electrical wiring, and condensate drain all need to be rerouted. It usually costs several hundred to over a thousand dollars. If your current location is causing problems, talk to an HVAC technician about whether relocation is worth it or whether other solutions (like a sound barrier or shade structure) would work better.