Have a New Home Addition? | Choose the Best Heat Pump for the Space

There are several options for the best type of heat pump to install in a small addition. They include a standard air source heat pump split system, a window unit heat pump and a minisplit heat pump. Let’s consider the best option.

The smallest standard heat pumps have 1.5 ton capacity, enough to serve a 600-750 square feet depending on the climate. That would be a fairly large addition and would involve the expense of installing duct work. For smaller additions, you’d be in danger of having a system that was too large, and there are several potential problems with that. First, you’d spend more than is necessary on the equipment. Secondly, the addition would heat and cool too rapidly, causing imbalanced temperatures throughout the space. Finally, when space cools too quickly in warm weather, the system doesn’t adequately dehumidify the air.

A window unit heat pump would also be an option. They come in sizes that can serve 350-700 square feet. They cost less than a standard heat pump system which is a significant factor for many homeowners. There are a few drawbacks that go with the cost savings. First, since the unit sits in the window rather than outside, they are nosier than standard heat pumps and minisplit ductless systems. Secondly, they are only about half as efficient as the most efficient minisplit systems so energy bills would be higher than needed. Finally, there’s the general inconvenience and security concerns of having to deal with a unit in the window.

Your third choice is the minisplit system. A ductless minisplit heat pump system is your best option for a small addition. First of all, your total equipment costs may be lower than those for installing a standard split system. For small spaces like a small addition, minisplit ductless heat pumps are competitively priced and you don’t have the expense of the duct work.

Secondly, the cost of installing a minisplit system is less than the cost of installing a full-size heat pump system. Next, with the high efficiencies offered by ductless systems, you’ll pay less in energy costs than a window unit and may also save versus a standard system. Thirdly, with a minisplit heat pump, you don’t have to find room for a standard air handler. The air handlers are small and mounted high on the wall or in the ceiling. Finally, knowing proper heat pump sizing will help your home have the most comfortable indoor climate in all seasons. You’ll experience balanced heating and cooling without temperature fluctuations. In warm weather, your comfort will be enhanced by the removal of excess humidity from the air.

While a ductless system may not be the right choice in all situations, a minisplit heat pump is ideal for a small addition where it will deliver efficient, comfortable climate control in all seasons.