Central air conditioning is a system that cools your home by distributing cooling throughout your home from a central unit using vents and ducts. An air conditioning unit that sits in your window, or a unit that is mounted on your wall or floor, is not central air conditioning.

A heat pump is a type of HVAC equipment that heats and cools your space by redistributing hot and cool air (rather than heating or cooling the air itself). Heat pumps are a very efficient and effective way of heating and cooling spaces. They’re often used to warm or cool down individual rooms, which enables you to turn down your central heating/cooling and reduce costs overall.

While conventional heating systems, like a furnace, are typically located inside the home and only produce heat, heat pump systems include a unit located outside of the home and can also be used for cooling. They also look very similar to an air conditioning (AC) unit.

Since heat pumps can look like air conditioners, here are some tips for telling them apart:

Since an AC unit generally needs to be paired with a heating system, try to locate a furnace or alternate system (e.g., oil, propane, boiler, etc.) in your home. If you can't find another method of heating, you may have a heat pump.
Set your thermostat to heat mode, and once you feel your home heating up, check to see if the outdoor unit is running. If it is, it’s a heat pump.
Find the manufacturer name and model number on the outdoor unit, and search the web for a product description of that model and more information.
Check for a yellow EnergyGuide label on the outdoor unit and look for the words "heat pump.”
Turn the power off to your system, then remove the thermostat display from its base. Check the wire terminal labeled O/B - if there’s a white wire or no wire, you likely have a conventional heating system instead of a heat pump.

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