Whether you’ve had an AC repair company install a programmable
thermostat or you are considering having one installed, there are a few
things that you need to know about how programmable thermostats work with
your heat pump.

In Cooling Mode

When in cooling mode, your heat pump’s operation is simple; it turns
on and off based on your temperature setting. A programmable thermostat
simply replaces a manual thermostat, which requires you to adjust the
temperature by hand. Since turning the heat pump off and on is the equivalent
of flipping a switch, any programmable thermostat will help you save energy
in cooling mode.

In Heating Mode

Heating mode is slightly more complicated because there are two parts to
a heat pump’s heating system. One source of heat is simply the reverse
of the cooling mode. This works basically the same way, automatically
turning on and off to control temperature, and uses about the same amount
of energy to heat as it does to cool. The second source of heat is a series
of coils inside the air handler. These use significantly more electricity
to run, but are only turned on when the air temperature is substantially
colder than the set temperature.

A basic programmable thermostat will usually use more energy to lower the
temperature 5 to 10 degrees while you are at work or sleeping. The electricity
that the secondary heating coils use to make up that temperature difference
will be greater than the electricity necessary to simply maintain a constant
temperature. If you’re looking to save money during heating season
as well, ask your AC repair company, Del-Air, about programmable
thermostats designed specifically for heat pumps that efficiently regulate
the temperature in heating mode.