Do heat pumps work in all types of homes?

A lot of articles written about heat pumps — including those on this site — assume that the reader is considering a heat pump for a single family home.

This is because this website is aimed at the North American market where single family houses are the most common type of home. However, heat pumps can be an option for other types of homes, including mobile homes and even apartments.

Some single family homes — especially older ones located in the Northeast — may have hot water or steam heat radiators. While air-to-water (also known as hydronic) heat pumps do exist and are useful for delivering both space heating and building hot water, they are more popular in Europe and potentially less desirable for the North American climate.

Thankfully, there different types of heat pumps that can be integrated into a wide variety of homes — not just single family houses.

If you want a heat pump for your home, the chances are that there’s an option for you. Whether or not they are economical options is another matter, so I’ll do my best to break it all down.

Heat pump options for homes with forced air HVAC

If you have a forced air heating or cooling system — that is, ducts that distribute air to rooms throughout the house — a central ducted heat pump will probably be your best choice, especially if you have an older central air conditioner that can be upgraded.

A central heat pump connects to an existing forced air system the same way that a central air conditioner does. The two main components of the system are a box-shaped outdoor condenser and an indoor heat exchanger that is installed next to the blower motor of the system. It looks nearly identical to a central air conditioner setup, except that a heat pump condenser can be larger.

This is a good choice if you have a forced air furnace. The heat pump will perform efficient air conditioning in the summer, and can provide a majority of your heating needs in the winter. When the temperature drops too low for the heat pump to be efficient, the system can switch over to the furnace.

While a cold climate heat pump can make it unnecessary to have a backup heat source, if you have a gas furnace that is still is decent shape, adding a non-cold climate model will be cheaper than a cold climate version. This configuration will let you continue to get value out of your gas furnace by maximizing its useful life, which could only be used for a couple of weeks a year.

Heat pump options for duplexes, townhouses, and smaller houses

If you have a duplex, a central heat pump can be a great option for the same reasons as it for a single family home, especially if there is an existing ducted system in place.

However, because duplexes tend to have less square footage than single family homes, ductless mini-splits are worth a close look. While ductless mini-splits can also be a good choice for single family homes, they can be less appealing when you have a lot of square footage because of the need to place indoor units in all of the areas where you want heating and cooling.

Indoor units, which take up wall space and can look cumbersome, is one of the main disadvantages of ductless systems, but this becomes less of an issue if you have a smaller home that needs fewer unit. This lets you gain the benefits from a ductless system, which includes zoned temperature control, and more flexible installation that doesn’t require utility room space.

Can you install a heat pump in an apartment or rental home?

When you don’t have the ability to make permanent alterations to your home, you still have options when it comes to heat pumps.

As a renter, the first thing you can do is talk to your landlord about the benefits of a heat pump. Federal tax incentives, in particular, can be appealing to a landlord who is looking for cost effective ways to maintain the mechanical systems of their rental property.

If your landlord isn’t sold, you can still install a heat pump using new designs that are an evolution of the familiar window air conditioner. These new models have a U-shaped saddle design that allow easy installation where you have a single- or double-hung window. The U-shape allows the unit to accommodate the larger heat exchangers needed by heat pumps.

Just like a standard window air conditioner, these heat pumps plug into a regular 120v power outlet. Unlike window air conditioners, these heat pumps can both heat and cool. They are also more efficient: Gradient claims that their heat pump can provide 9,000 BTU of heat per hour in outdoor temperatures as cold as 17°F, and still generate 5,400 BTU/hr when it gets as cold as -7°F. This compares favorably to an electric space heater, which will produce only about 5,100 BTUs per hour while drawing the maximum 1,500 Watts from a 120v outlet.

Heat pump options for homes in an HOA community

If you live under a homeowner’s association, you’ll be familiar with the rules they can impose, including those governing seemingly minor appearance issues such as paint color and the kinds of lawn decorations you can have.

Unfortunately, heat pumps (and air conditioners too) can run afoul of HOA rules because of the need for outdoor units (which alter the appearance of the home). Heat pumps also require drilling a small hole in an outdoor wall for a refrigerant line, which an HOA may consider to be a structural change.

If you find yourself in this situation, your first step should always be to try to work with the HOA, especially educating them on what heat pumps are and what their benefits are. If the HOA is okay with with installing central air, there should be no reason why they wouldn’t allow heat pumps too. If the appearance of the outdoor condenser is an issue, there are low profile units that are compatible with both ducted and ductless setups. Low profile units are less bulky and easier to hide.

You can also hide outdoor units behind a fence or landscaping as long as there is a sufficient air gap around the unit.

If your HOA still wants to block the installation of a heat pump despite these options, another recourse is to check your state laws. In some states, such as Washington, there are laws that limit the power of HOAs to restrict the installation of a heat pump. Here’s a relevant snippet from Washington’s law ¹:

(1)(a) A homeowners' association may not adopt or enforce a restriction, covenant, condition, bylaw, rule, regulation, provision of a governing document, or master deed provision that:
(i) Effectively prohibits or unreasonably restricts the installation or use of a heat pump in compliance with the requirements of this section and for the personal use of an owner within the boundaries of a lot; or
(ii) Is in conflict with the provisions of this section.
(b) Nothing in this section prohibits an association from imposing reasonable restrictions on heat pumps.
(c) This section must not be construed to permit installation by an owner of heat pump equipment on or in common areas without approval of the board of directors.

Note that Washington’s law includes a “reasonable restriction” clause, which means that the restriction can’t significantly add to the cost of a heat pump or reduce its performance. But because of the ambiguity of the wording, you might still find yourself in a fight with the HOA even if the law is on your side.

Heat pump options for a mobile home

Ductless mini splits are usually the best option for mobile or manufactured homes, even if the home has a forced air furnace. This is because furnaces designed for mobile homes tend to have smaller dimensions, and the indoor heat exchanger (also known as the cased coil) for the heat pump you want may not be available in a compatible size.

In contrast, ductless mini splits have fewer limitations on where they can be installed. They’re also a great choice for the smaller square footage of a mobile home.

Heat pump options for homes with existing radiators

Forced air is the most popular type of residential HVAC system in North America, but hydronic heating systems are also common, especially in the Northeast and in older homes. Hydronic heating systems use hot water to transport heat to radiators or in-floor piping.

Hydronic heating systems have benefits compared to forced air, including quiet operation and fewer air drafts.

Air source heat pumps can work with hydronic heating systems. These are known as air-to-water heat pumps, and they’re more popular in Europe than in North America. In this type of heat pump, the heat pump is used to create hot water that is circulated to radiators or in-floor loops. The limitation of heat pumps is that they can only be used with low temperature hot water heating systems.

Some old houses in the Northeast have high temperature hot water heating systems (ie. steam). Unfortunately, you can’t retrofit a heat pump into this type of system, so if your old house has steam radiators, you’ll need to either replace the radiator system or install mini splits if you want to switch to a heat pump.

Heat pumps, however, are compatible with low temperature hot water systems, which include in-floor radiant heating. These systems are great if you want a system that provides quiet, even heating.

Disadvantages of hydronic heat pumps

One reason that hydronic systems are more popular in Europe is that air conditioning is less of a requirement, although this is starting to change as climate change causes summer heat waves to be more common. While hydronic cooling is used in commercial applications, it’s much less common for residential installations. The radiators that are used to provide heating in a hydronic heat pump system can’t be used for cooling because of the need to remove condensation from the heat exchanger.

Instead, hydronic cooling systems rely on a fan to blow air over the heat exchanger and a drainage system to remove moisture. In other words, the indoor unit of a hydronic air conditioning system looks a lot like the indoor unit of a ducted mini split. Because of this, air-to-air heat pumps with ductless mini splits are the more popular type of system.

That said, there are some advantages of hydronic cooling, such as eliminating the need for indoor refrigerant lines. (In a hydronic system, heating and cooling energy is transported with water instead of refrigerant.) Multiaqua ² is one of the few North American companies that provides hydronic heating and cooling systems for residential applications.

Bottom line: heat pumps can be a viable choice in nearly any home

If you’re interested in a heat pump system, chances are that there is an option for you. Even if you’re a renter, new heat pump designs make it possible to temporarily install a window heat pump that you can take with you if you decide to move. And while it may not always be possible to retrofit heat pumps into the the high temperature hot water heating systems found in some older homes, it’s almost always an option to install a ducted mini split alongside the existing heat system to add air conditioning or supplemental heat.

Whether or not it makes economic sense is another thing, but tax incentives certainly help with that. Be sure to find at least a couple qualified contractors and get competing quotes. You can use the links on this page to get started.

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