Mini split heat pump

Need help sizing a heat pump? 

EnergySmart of VT is here for you! 


February 25, 2021

Heat pumps are one of the most efficient heating and cooling systems on the market, and installing one in your Washington County, Vermont home could lead to greater comfort and help you save significantly on your energy bills. 

But heat pump efficiency depends heavily on correct sizing, and if you choose a system that’s too big or too small, you could end up with an uncomfortable home that wastes energy and costs a lot of money to heat and cool. 

The Problem With Over and Undersized Heat Pumps 

Sizing issues are extremely common when it comes to heat pumps, and they can lead to costly problems. 

When a heat pump is too big, it will reach the set temperature quickly and then shut off right away—a process referred to as short-cycling. When HVAC systems short-cycle, they waste energy and cause inconsistent temperatures throughout the home, which is uncomfortable for occupants. Short-cycling can drive up your energy costs and cause excess wear and tear that can lead to expensive repairs and premature system failure. 

When a heat pump is too small, on the other hand, it won’t be able to meet heating and cooling demands, making the home uncomfortable. It will also have to work much harder, sometimes even nonstop, to reach thermostat settings, which takes a lot of energy and can cause breakdowns. 

How Do You Size a Heat Pump? 

Heat pump sizing can be a complicated process that takes many factors into account, including: 

  • The square footage of your home 

  • The local climate 

  • The number, size, and location of windows 

  • The number of people who live in your home 

  • Other appliances in the home that generate heat, like your water heater 

In the United States, a Manual J load calculation is the standard for determining HVAC size. Using the Manual J system, HVAC contractors can estimate the number of British Thermal Units (BTUs) needed to reach the heating and cooling load of a home. Special software is used to make these calculations. 

While it may be possible to size a heat pump yourself, it is typically best to have an experienced HVAC contractor handle the calculations for you. Leaving this important process in the hands of a trusted professional will guarantee you receive accurate results, preventing the risk of costly mistakes and ensuring your new heat pump maximizes comfort and energy efficiency. 

Expert Heat Pump Sizing and Installation for Vermont Homeowners 

The team at EnergySmart of VT is well-versed in the proper methods for sizing heat pumps. Our cold climate heat pumps are perfect for homeowners in Barre and throughout all of Washington County, VT, and we can make sure your new heat pump provides the comfort and efficiency you’re looking for by sizing and installing it in accordance with industry best practices. 

We can also help you qualify for incentive programs, like the Efficiency Vermont heat pump rebate, to make your energy-efficient HVAC upgrade as affordable as possible. Since our founding more than 30 years ago, we’ve been dedicated to improving the performance of our customers’ homes, and our team uses building science to deliver on our promises of better efficiency and comfort. 

Looking for the right size heat pump for your Vermont home? EnergySmart of VT can help. Call 802-476-3549 or contact us here to schedule a consultation.