Conventional Forced Air: If you have a heating and cooling system with vents that warm or cool air blow out of, you have a forced air system
Heat Pump: A heat pump is like a standard air conditioner except that it provides both heating and cooling. Typically your thermostat will have an O or B wire connected in order to switch between heating and cooling.
Radiant: Heating systems that circulate water or steam through pipes or radiators from a boiler

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What is the difference between Conventional Forced Air, Heat Pump, Radiant, Other, and None

Conventional Forced Air is used to describe systems such as gas furnaces with central air conditioning tha blow air through vents. Heat pumps also blow air through ducts, however a heat pump uses one outdoor unit to control both air conditioning and heating. Radiant systems use hot water to heat the home. This may be done with baseboards or radiators. If you do not have one of these types of systems select Other and we will help you set the system up appropriately. If the Lyric Thermostat is only controlling air conditioning in your home select None (Cool Only)

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