How It Works: Inverter Heat Pumps

Heat pumps are machines used to transfer heat from one area to another. They are typically used to pull outside heat into a home or commercial building. The term describes many HVAC devices used to heat or cool an area. Although it sounds contradictory to the term, air conditioners and freezers are common heat pumps. The pump systems work at a high level of efficiency and keep energy bills low.

Traditional Heat Pumps
The refrigerant travels between the compressor and condenser during a refrigerant cycle. In this cycle the refrigerant transforms from liquid to gas. When the home reaches the desired temperature the refrigerant cycle stops and only re-starts when the home temperature goes outside the temperature specified on the thermostat. When the system stops and restarts, the pump system consumes energy to bring itself up to the correct temperature to begin heating or cooling.

Inverter Systems
Inverter systems are even more efficient because the pump reduces energy lost during the refrigerant cycle. In these heat pumps fitted with an inverter, or variable speed compressor, the refrigeration cycle runs at different speeds which are dependent on the temperature and heating loads. The inverter adjusts the speed of the refrigerant eliminating energy loss caused by restarting the machine each time the temperature levels change.

To keep your heat pump running efficiently the system should be serviced annually. During service your service technician will inspect all the ducts, refrigerant levels, air flow levels and all the electrical connections. During the check up your filter should be changed and belts lubricated.

Efficiency is also dependent on using your thermostat correctly. The thermostat should not be moved more than a degree or two at a time because the heat pump's back up system will engage. Starting the back up system will utilize the system's electric coils costing on your energy bills. Allow time for your the machine to catch up through its normal running system before making further changes on your thermostat. The ductwork connected to your heat pump should be tightly sealed in order to increase the efficiency of the unit. The airflow of the unit also depends on keeping the system clear of any plant growth or other physical barriers that could impede air intake. Clogging the air intake will drain the system and raise your utility bills.

Tax Credits
Depending on your location, you may be eligible to receive federal or state tax credits for installing an inverter heat pump. The system's energy efficiency rating is extremely high however, not all Energy Star certified pumps meet the standards for tax credits. If you're looking to benefit from tax credits, make sure to check the local requirements of heating systems.