Heat Pumps – Frequently Asked Questions
Will a heat pump reduce my annual heating costs?
While every home is different, in a typical Maine home, a ductless heat pump will reduce overall heating costs as long as it is used enough. Customers with an oil boiler can save $300 to $600 if they follow Efficiency Maine’s Ductless Heat Pump User Tips.
How many ductless heat pumps has Efficiency Maine rebated?
How many ductless heat pump installers are there in Maine?
Over 500 from York to Fort Kent. Click here to find one near you.
Do ductless heat pumps work in cold weather?
Yes. The high efficiency units that qualify for Efficiency Maine rebates work well in cold weather. Some are rated to work down to -15°F.
Do they produce enough heat for an entire home or business?
It depends on the building, heat pump, number of indoor units and outdoor temperature. If you’re looking for a whole-building solution, be sure to let your installer know. A growing number of homes and businesses in Maine are designed to heat and cool entirely with heat pumps.
How do rebate-qualifying heat pumps compare with ones that don’t qualify for rebates?
Qualifying units are more efficient at producing heat than non-qualifying units when outside temperatures are low. This enables qualifying units to produce more heat than non-qualifying units.
Is there a temperature below which a conventional heating system is cheaper to run than a heat pump?
Yes, for some heat pump/boiler combinations and electricity/heating fuel price ratios there is an outdoor temperature below which the boiler burning oil or propane is less expensive to operate. Our modeling has shown that using 2018 energy prices, the transition point is somewhere between 5F and -15F. Switching back and forth exactly when the temperature crosses the transition point could save up to 5% on heating costs. However, forgetting to switch back to the heat pump once the temperature climbs back above the transition point could end up costing more. Therefore, we generally recommend that you select a temperature set point on the heat pump that makes the room feel comfortable (usually several degrees higher than what you have used with your central heating system thermostat) and leave it at that setting throughout the winter.
Do I need to replace my current heating system if I want to use a ductless heat pump?
No. Though high-efficiency ductless heat pumps may be configured to work as the sole heating system, they are often used to supplement an existing system (for example, by installing a heat pump in one room and and using the central oil boiler system to heat the rest of the building).
How many rooms can I heat with a ductless heat pump system?
A single indoor unit can heat several rooms as long as there is a path for the heat to travel between them. Some homeowners keep doors open to maximize the ability of their heat pump to heat multiple rooms. Another approach is to use multiple indoor units to heat different rooms.
What else can they do beyond heating?
High-efficiency ductless heat pumps perform the same functions as five different appliances: heaters, air conditioners, dehumidifiers, ceiling fans, and room air filter.
Do they bring in fresh air?
No. Heat pumps move heat from the outside of the house to the inside. While they do not bring in fresh air, they do recirculate and filter indoor air.
Will a ductless heat pump increase my electric bill?
Unless you use electric resistance heat for your home or business, a ductless heat pump will increase your electric bill. However, if your current heating system runs on oil or propane, the savings from burning less oil or propane will exceed the increased cost of electricity. When a ductless heat pump is used for cooling instead of a window air conditioner, it will decrease your electric bill. In addition, a high-efficiency model that qualifies for Efficiency Maine rebates will cost less to operate than standard efficiency ductless heat pumps.
Can I offset household carbon emissions by using a heat pump?
Heat pumps use electricity to heat your home, so their carbon footprint depends on the power generation that serves the regional energy grid. The mix of generation that serves the grid in Maine is among the cleanest in the country. If you have a ductless heat pump that offsets just one third of your home’s annual heating load, and if you heat with oil like most Mainers, the heat pump would eliminate 2,400 pounds of CO₂ per year, the equivalent of eliminating the carbon pollution from three months of average driving. The more your heat pump offsets your home’s heating from fossil fuels, the more you will reduce your carbon emissions.