When these babies kick in, you can go outside and watch your meter run laps around the house! OK, I’m exaggerating, but this is where it can get very costly. Just prior to the electric resistance coming on, the air that is supposed to be providing heat is actually getting cool.

Are you starting to see the “why”?

Now we’ll talk a little more about the heating cycle of the heat pump. The idea is that during the heating cycle, the heat pump’s outdoor coil is going to absorb heat from the outside air. Let’s think about that. The last time you were outside in 40 degree weather, or even lower temperatures, were you wearing a T-shirt, sweating like a pig, and wishing you had a nice, cold glass of iced tea? I didn’t think so. Would you agree that there is not very much warm air available below 40 degrees? All I’m trying to say is that in areas with climates that typically stay above 50 degrees, a heat pump is a great source of economical comfort. However, I live in northeastern Pennsylvania. In this type of climate, it’s time to incorporate a “heat pump helper.”

Auxiliary Heat

One other thing to keep in mind is that when a heat pump goes into the defrost cycle, it is actually going into the cooling cycle only. The outdoor fan stays off so the hot refrigerant gases can melt any ice that may be building up on the unit. This heat is being taken from the home you are trying to heat.

Guess what else happens? So you don’t feel the cold air from the cooling cycle, the good, old, reliable electric resistance heating element comes on to keep you warm. Does that sound very efficient? Of course not. That’s why, once again, I want to stress that in climates that drop below 40 degrees, the heat pump helper is the way to go.

This is what’s known as a hydro-air system. You can use a hot water heater or boiler to produce hot water. The hot water is piped to an air handler, sometimes called a fancoil. Inside the air handler is a multirow coil, through which hot water is circulated. Air is then passed over the coil and ducted to the living space.

You’ll be hard pressed to find a more comfortable and economical heat pump system in areas like the one I live in.

Here’s one more great advantage this system brings to your customers: If they are heating their domestic water with an electric water heater, which is expensive, they no longer need that; they can utilize the coil from a boiler or install an indirect storage tank. Or, of course, they could use a system like the one described earlier.

Mercurio is the owner and sole proprietor of Oil Tech Talk (www.oiltechtalk.com), which offers the heating industry continued education through books, seminars, in-house training, and consulting. Mercurio is an associate trainer for Bacharach Inc., and he is the immediate past president and founder of the Susquehanna Valley Chapter of the National Association of Oilheating Service Managers (NAOHSM) and the current education chairperson.

Publication date: 05/19/2003