Air to water heat pumps use the same concept as an air source heat pump for drawing heat from the outdoor air. The difference is it delivers the heat via water piped through a home, multifamily property or business (rather than hot air).
Residential
Air to Water Heat Pump Incentive
Available when replacing an existing heat pump, or adding a heat pump to a previously unconditioned space.
Energy Optimization Incentive
Available for homeowners replacing natural gas, oil, propane, or electric resistance as the primary heating source with an energy-efficient heat pump. This rebate helps maximize savings and comfort when upgrading your heating system.
Benefits
- Comfort: Enjoy reliable heating and water heating from a single system. Air to water heat pumps maintain consistent temperatures and perform efficiently even in cold climates, all while operating quietly and providing enhanced comfort.
- Flexibility: Air to water heat pumps offer versatile solutions for a wide range of applications. They are ideal for space heating when paired with underfloor heating systems, fan coil units, or appropriately designed radiators. Additionally, they can efficiently supply domestic hot water to meet everyday needs.
Note: Compatibility with existing radiators depends on their design and the water temperature they were built to accommodate. |
- Efficiency: Transferring heat using water provides a reliable and effective solution for heating and hot water. Air to water heat pumps offer steady performance, helping to reduce energy consumption and lower heating and water heating costs.
- Environmental impact: Reduce your carbon footprint by emitting less greenhouse gas emissions.
Incentives & Financing
Single Family (1-4 housing units)
INCENTIVES
Air to Water Heat Pump Incentive: $250 per ton, up to $15,000 combined incentives for qualifying models
Energy Optimization Incentive: $500 per ton, up to $15,000 combined incentives for qualifying models
Federal tax credits may be available. Learn more about the IRA tax credits here or speak to your tax preparer.
FINANCING
Multifamily (5 or more housing units)
INCENTIVES
Market Rate: $750/ton when displacing electric, oil/propane, and natural gas
Income Eligible: $1,875/ton when displacing electric and oil/propane, $750/ton when displacing natural gas
FINANCING
Information & Tips
Air to water heat pumps efficiently distribute hot water through radiant heating systems, making them well-suited for homes and businesses with existing hydronic infrastructure, such as radiant floors and certain types of radiators.
Unlike conventional boilers, air to water heat pumps operate at lower water temperatures, which can affect compatibility with some existing radiant heating systems. However, in-floor and in-ceiling radiant heating systems work particularly well with air to water heat pumps due to their large surface areas for heat transfer. In well insulated, energy-efficient homes, these heat pumps can also be paired effectively with low temperature hydronic baseboard radiators.
- Efficiency First: Before installing a heat pump, weatherize your home or multifamily property to enhance comfort, reduce energy use and greenhouse gas emissions, and improve equipment efficiency and lifespan.
Air to water heat pumps are available in two main configurations: split systems and monoblocs.
Split systems consist of an outdoor unit, typically installed on the ground, and an indoor unit with a buffer tank located in the utility space. These systems distribute heat through radiant heating zones in the living space, which are controlled remotely. The indoor and outdoor units are connected by small refrigerant lines that transfer heat between them.
Monobloc systems house all components within a single outdoor unit, eliminating the need for refrigerant lines between separate units.
Both configurations require a buffer tank, radiant heating distribution zones, and controls for operation.
Air to water heat pumps use a hydronic system to deliver heat and hot water. The outdoor unit extracts heat from the ambient air and transfers it via refrigerant to an indoor unit, which then distributes it throughout the home.
These systems work efficiently with radiant heating systems, such as in-floor or in-ceiling installations, providing consistent and comfortable warmth.
To select the right heat pump for your home or multifamily property, consult with a qualified contractor that participates in the Energize CT Heat Pump Installer Network.
If you find a system that is listed on the Energize CT Heat Pump Qualified Products List (PROVIDE LINK), and qualifies based on our Efficiency Ratings Chart, your contractor can purchase a qualifying air to water heat pump on your behalf, allowing you to benefit from instant discounts. After installation, check with your contractor to find out if you're eligible for an additional energy optimization rebate.
Air to water heat pumps require integration with a hydronic heating system (radiators or underfloor heating) and may involve more complex installation. However, they are better suited for larger homes or commercial properties needing high-efficiency space heating and hot water.
Compare the annual cost and carbon emissions savings from investing in a new heating and cooling system. The Clean Heating & Cooling Calculator can help you see how much upgrading your system to heat pumps would reduce your carbon emissions – and what it would mean for your home’s budget.
How Air to Water Heat Pumps Work
Air to water heat pumps transfer heat to water, which is then circulated through radiators, underfloor heating systems or stored in a hot water tank for domestic use. They are used for space heating, hot water production, and sometimes cooling.
Other Helpful Resources
Other Helpful Resources
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Learn more about heat pumps
Download the heat pump brochure.
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Heat pump user tips
Get the most from your heat pump.
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Questions for your installer
Download a list of questions you can ask your installer.
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Quality installation checklist
Download the Air Source Heat Pump Quality Installation Check-list.
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Explore Clean Heating and Cooling Technologies
Explore a variety of clean heating and cooling technologies designed to enhance comfort and efficiency while reducing energy costs.
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Also Explore ➞
Home Energy Assessments
- Request an energy assessment of your home.
- Receive customized energy-saving recommendations.
- Get help implementing energy-saving measures from a technician or receive rebates and incentives to implement them yourself.
