Conventional water heaters have units that create heat to warm the water in the tank. Whereas, heat pump water heaters use heat you already have to warm the water in your home. These water heaters are far more efficient at conserving and using electricity than your conventional water heater. In fact, heat pump water heatersgenerate about twice as much hot waterfrom the same amount of electricity as conventional water heaters.
How They Work:
The common metaphor is that they are a refrigerator in reverse. Where refrigerators pulls out warm air and try to cool the space inside, heat pump water heaters bring in heat you already have in your HVAC system to heat water. Just as its easier to tailor a pair of pants than to make some from scratch, moving heat is much, much easier than generating it. So why not work with what you have?
Our friends atGreen Building Advisor can explain the technical terms pretty well:
“[A] heat-pump water heater uses electricity to move heat from one place to another–in this case, from the surrounding air where the unit is located into the water.This is done by circulating a special “refrigerant” fluid that can be alternately evaporated into a gas and condensed into a liquid by changing its pressure.
Surrounding air is drawn into the heat pump where the heat in that air vaporizes refrigerant in the “evaporator,” releasing cooler air into the room. The refrigerant vapor is then pumped through a “compressor” where it condenses back into liquid form and releases its stored heat into the water.”
In other words, the system sucks heat from a warm room and uses it to heat water. The downside? The heat pump system needs to be near a heat source to actually help you save energy and money. Yet, if you have a furnace that radiates heat or you use a wood stove to heat your home, a heat pump water heater can use some of that extra energy to warm up your water rather than using electricity or other expensive sources like conventional water heaters.
Meanwhile, if you live in a comfortable climate like we do here in Sacramento, heat pump water heaters are great partial air-conditioning units, because they suck in warm air as well as moisture!
The downside is that you need a sufficient amount of heat in the environment to warm the water. Placement of the system here is key, and whether or you can store them outdoors or indoors will vary on your model. California is an ideal climate for outdoor storage, meaning you can harness the free energy from the sun to warm a containment cell that will create warm air for the unit to use. Kind of like walking into a hot shed in the summer. Otherwise, an HVAC specialist will be able to advise you on how and if a heat pump water heater can work for you.
When upgrading your water heating system, or looking for additional alternatives to reduce your utility bill, it’s important to weigh all your options. Heat pump water heaters can be a great option to California residents and we encourage you to contact us if you have any questions.