In
climates that have heating seasons, when people seek to buy an air
conditioner, they should instead purchase a heat pump. The cost
increase for buying a heat pump instead of an air conditioner is modest, and
the heat pump can do both heating and cooling.
Heat pumps are more complex than electric resistance heat, and less familiar than natural gas furnaces. Approach heat pump projects carefully.
Before you buy
Incentives. If you have the time, before investing in a HPWH, look
into the financial incentives that are available. The requirements and
guidelines of the various incentive programs may help guide you in
selection of equipment and installer.
Federal,
state, and local governments may be offering tax and other incentives
for heat pumps, to encourage electrification and
conservation of energy. https://www.dsireusa.org/ https://www.energystar.gov/about/federal-tax-credits
Your local electric utility may also offer heat pump incentives to promote energy conservation and/or electrification.
Consider bringing down the cost of your heat pump by first making your house more efficient. Your heat pump price will depend in part on the size--the
capacity--of the heat pump. Before buying a heat pump, look at ways to
reduce the heating and cooling requirements of your house, through
insulation, double pane windows, weatherstripping, window shades, etc.
Such changes may reduce the size of the heat pump you buy, and will also
reduce the amount of energy the heat pump uses once it's purchased.
What to look for in a heat pump
Noise ratings (sones). Quiet is good. There are likely to be two noise ratings of interest: the fan that supplies the air to the conditioned space, and the noise of the equipment that contains the compressor.
Efficiency ratings. High efficiency is good. Energy Star certifies efficient equipment, and offers product information, including efficiency ratings, on their website. A heat pump has at least two efficiency ratings: for heating and for cooling. The efficiency of a heat pump drops when the outside air temperature drops, so explore the low-temperature efficiency of the heat pump.
Cold Climates. Some heat pumps are designed specifically for
cold climates. Explore these options if your climate has cold winters.
Typically variable speed drives on fans and compressors are a sign of
quality. They allow the equipment to respond efficiently--and often
more quietly--to variations in the amount of work that needs to be
done. Find out what your heat pump does at freezing outside
temperatures. Does it use backup electric resistance heat? Down to
what outside air temperature (and up to what outside air temperature for
cooling) should the heat pump be able to maintain comfort in the space
it serves? Is your heat pump being sized to meet the heating load or
the cooling load, or both, for your climate?
Ductless Heat Pumps. If you need to cool only one or two
rooms in the house, consider installing "ductless" heat pumps, or
"mini-splits". There's a inside unit that goes high on the wall. It
contains a refrigerant heat exchanger and a small fan. The outside unit
contains a refrigerant heat exchanger, a fan, and a compressor. The
outside unit will need to have some clearance so that outside air can
flow freely around the heat exchanger. Be sure the noise rating for the
outside unit is low enough to accomodate its location, particularly if
it's right outside a bedroom. Typically a ductless heat pump serves a
single room, so each room has its own control. Sometimes people install
ductless heat pumps in some rooms, where they want to add air
conditioning, and leave old baseboards in other rooms.
What to look for in a heat pump system
Ductwork. If the heat pump is going to be hooked up to old ductwork that was used by a furnace, check that the ductwork is big enough to use with a heat pump. Normally the ductwork serving a heat pump is larger than the ductwork serving a furnace, because the air heated by a heat pump isn't normally as hot as the air heated by a furnace.
If you have ductwork that runs through unconditioned space, as in the
basement, minimize air leaks at the duct seams, and insulated the
ducts.
Temperature Setback at Night. Heat pump manufacturers often tell customers they shouldn't change the temperature settings on the heat pump thermostat. If you want to have your bedroom cool down at night (a healthy thing to do), you may prefer not to have a heat pump serve your bedroom.
Thermostat. Take the time to understand the thermostat, and ask for clarification if something's confusing. Heat pumps are complicated. Excessively noisy fans and ductwork are not only noisy but they also waste energy. If the fans are too noisy in the house, ask whether or not the airflow can be reduced without creating a problem for the heat pump. The thermostat should be located far enough from the heat pump that it's measuring a mixed air temperature, not the temperature of the air coming directly from the heat pump. Anticipate the fact that normal heat pumps don't heat up a house as fast as a normal furnace. This is because heat pumps normally deliver air at a milder temperature. For this reason, manufacturers discourage radical changes to the thermostat setpoint when using a heat pump.
7/16/24