A question we are often asked is, “what size heat pump do I need?”. While this may seem like an innocent question with an easy answer, the reality is very complicated. Determining the size of your geothermal heat pump involves complex calculations and terms like “U-factor” and “winter design temperature”, and is the most important part of your installation. Correctly sizing your heat pump is important because in cold areas like Canada and New England, under sizing your heat pump could result in your home being chilly during the dead of winter. Let’s look at the process behind scientifically determining how large your heat pump should be, and why it’s important for your New England heat pump installation project.
How to Correctly Determine The Size Of Your Heat Pump in New England
The only correct way to determine how large your geothermal heat pump should be is to do a heat load analysis. Usually performed using software such as Wrightsoft, a heat load analysis takes many variables into consideration to determine how much heat your home needs. Variables such as the size of your home, how many windows it has, whether there’s a basement, and the type of insulation you have are all factors.
The software also takes into account the location of your home. Your location is important because the colder the outdoor temperature, the higher the rate of heat loss. That is why it takes more heat to maintain a comfortable indoor temperature in cold climates like Canada or New England than in temperate climates like Florida or British Columbia.
Your geothermal heat pump installer will input all of these variables into the software, which will use industry standard calculations to determine your home’s heat load. The heat load is how many Btu’s per hour your heat pump needs to produce to maintain an indoor temperature of 70°F (21°C) on the coldest night of the year. Then your installer will match this requirement to the output of the heat pump to determine the correct size.
Be Cautious With Ballpark Figures for Your New England Heat Pump Installation
Some installers don’t do a formal heat load analysis. Instead, they use ballpark figures such as a certain number of Btu’s per square foot. Or they’ll use your current heating bills as a reference. It’s possible to get a general estimate of how much heat your home needs using these methods, but the chances of under sizing your heat pump are much higher. We don’t recommend ballparking your heat pump’s size. In fact, it’s one of the top four questions we recommend you ask your geothermal heat pump installer.
What Happens When Your New England Heat Pump is Undersized
The downside of under sizing your heat pump is that it will not be able to provide you with enough heat on the coldest days of the year, even if it runs continuously. The potential to undersize your heat pump is the main reason that, if you called us up, we wouldn’t be able to tell you what size heat pump you need. Because if we get it wrong and you undersize your heat pump, you’ll be cold on the coldest night (or nights, depending on how undersized the system is) of the year.
Ending up with a heat pump that is too small is easy to avoid: simply do your homework and make sure you find a dealer in your area that will do a heat load analysis before estimating how large your home’s heat pump should be. To find out more about how geothermal heat pumps can work for you, download our ebook below:
Learn how geothermal heat pumps can help you save up to 75% on your home heating costs with our ebook: Geothermal Energy: Consistent, Comfortable and Cost Effective Heating and Cooling For Your Home.