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A heat pump is a central forced air heating and cooling system equipped with a thermostat. Most heat pumps are called "air source" heat pumps because they derive their heat from the outside air. They have two main parts, an outdoor unit with a heat exchanger, compressor and fan, and an indoor unit with a heat exchanger and air handler. Another type of heat pump is called a "water source" heat pump. This type of heat pump has one unit with two heat exchangers, a compressor, and an air handler. Both types have reversing valves for cooling.

The heat is transferred through an inside coil and then distributed through ducts. By reversing the cycle, the system will act as an air conditioner. A heat pump does not generate heat like other heating systems. Instead, it moves heat from one place to another.
How do you operate heat pumps?

The thermostat starts or shuts off the refrigeration cycle according to the set temperature. If for some reason the heat pump cannot maintain the desired temperature, the backup heat comes on. When the set temperature is sensed by the thermostat, the system shuts off.

Adjusting the thermostat up and down can force the backup heat to come on and will increase the cost of operation, unless you have a "smart" thermostat, which brings up the heat slowly and prevents the back up heat from coming on.

Many thermostats do not accurately measure the room temperature. This means that although you set the thermostat to 68 degrees it may actually allow the room temperature to climb several degrees higher than your "set point" before shutting the system off. To check the accuracy of your thermostat, place a thermometer in a central location in the room. Check the thermometer reading against the reading on your thermostat. Are they the same? Experiment with the thermostat so you will know where to set it next time. Remember, the lower you keep the temperature setting, the lower your energy costs.

Heat pump options
There are many options available for heat pumps. These include: clock thermostats, a variety of compressors, electronic controls and electrostatic filters.

What Does It Cost To Operate A Heat Pump?
An efficient heat pump uses approximately one-third the energy of a resistance heating system, such as electric forced air. When including backup heat and defrost cycle, a heat pump averages about one-half the cost of electric forced air heat. You can reduce the operation cost further by using a "smart" thermostat and setting it at 68 degrees.

If the auxiliary or emergency heat light is always on when the unit is running, there is some problem with the system. It could be a clogged or dirty filter, blocked registers, debris on the outside coil, the compressor may be low on refrigerant, or there could be other internal problems. If there is an increase in electrical usage for no apparent reason, the compressor may not be working and you may be operating expensive back-up heat.