Advantages  Factors to Consider   Incentives    Resources   Shopping/Installing   How HPWHs Work


Heat Pump Water Heaters Save Money & Are Better For You

MORE EFFICIENT. Just as heat pumps warm the air in your house, heat pump water heaters (HPWH) heat your water for showers, dishwashing, laundry and other needs. Because they don’t create heat, only collect it from the surrounding air, they are 2-3 times more efficient than most current hot water systems.  HPWHs can save you hundreds of dollars per year.

They can also be better for your health compared to methane (natural) gas and propane heaters.  The least expensive gas water heaters use atmospheric venting (no fan) and waste energy by Black and white photo of two young children in the bathtubventing warm air, combustion gases like CO2, carbon monoxide, nitrogen oxides, and acidic water vapor through a pipe, chimney or flue to the outside. If the venting system is improperly installed, backdrafting may occur, in which exhaust gases are pulled back into the house. According to one contractor, “this is a common defect identified during home inspections, and it’s almost always a condition that the homeowner or occupant is not aware of.” Another site notes that backdrafting can
start after sealing the house for leaks during weatherization; the water heater, unable to get enough air for combustion, pulls it back through the flue. This is not only a
health hazard, but the corrosive liquid can eat through metal and cause the heater to leak.

BETTER THAN TANKLESS. Tankless  (or Instant)  gas water heaters are sold as a more efficient energy saving solution because they only burn fuel to heat water when it is needed.  However, they emit two times the amount of unburned methane than large gas tank heaters. This is because they turn on their burners more frequently, and each time, they release a puff of unburned methane, which is 84 times more potent at warming than CO2 over a 20 year period.  HPWHs are the most efficient water heaters, and you do not have to worry about carbon monoxide poisoning or the effects of other combustion products from improperly installed or vented fossil-fuel burning water heaters.
INCENTIVES. Taxpayers are eligible NOW for 30% tax credit ($2,000 max/year) for HPWH +  30% tax credit ($600 max) for electrical panel upgrade if needed. Low- and middle-income households will be eligible for 100% or 50% rebates ($1,750 max) LATER.  See Incentives below for more.

Important factors to consider

    • Emergency. Water heater purchases are often made when the current heater fails and a new one is needed right away.  Take the time now to learn about how heat pump water heaters can save you money in the long run and protect your health.  
    • Location. HPWHs will slightly cool the room they are in. The cool air they expel can be vented outside if this is a problem. They perform best in locations that remain in the 40–90 degrees F range and that have access to 750 – 1,000 cubic feet of air (so closets are not ideal-add louvers to doors if no other places are available). They also need a drain or pump for the clean condensate water the HPWH releases. 
    • Size. Be aware that HPWHs can be larger and taller than conventional water heaters. If space is limited, consider an ENERGY STAR certified split system (see photo to the left). Smaller companies Nyle and Eco2 Systems make split system HPWH (with a separate condenser). 
    • If you are replacing a gas water heater with a HPWH, you may have to upgrade your electric panel because the most common type of HPWH requires a dedicated 240 Volt outlet.  Rheem recently released two HPWHs that can use existing 120 volt outlets, and it is expected that other manufacturers will follow suit. Because they plug into a wall outlet and don’t require any special wiring, 120-volt HPWHs will have lower installation costs and further increase household savings.
    • If you decide to upgrade your electric panel to create a 240 volt outlet for a new HPWH you can use the 30% (25C) tax credit up to $600 for an electrical panel upgrade, but only if you do that work in conjunction with another upgrade covered by 25C (like a HPWH).
    • Search for “heat pump water heater” and “Hybrid High Efficiency” when shopping. Most heat pump water heaters are called hybrid because they come with an electric heating element as backup.