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HVAC Education, Buying Tips, Furnaces, Heat Pumps, Technology

What is a Split System?

A split system is an HVAC system that has both indoor and outdoor units that are connected with copper tubing. There are many different types of split systems, which can include either a heat pump or air conditioner (larger homes might require multiple air conditioners) installed outside your home, paired with either a gas furnace or a fan coil located inside your home.

what is a split system

Heat pumps

Heat pumps run on electricity and draw heat from outside air—even cold air—and transfer it indoors. The outdoor unit houses a compressor and heat exchanger, and the indoor unit has an air handler and fan that circulate the air inside the home.

Air conditioners

Split-system air conditioners are units with the condenser and compressor placed outdoors, and an indoor unit containing the evaporator, furnace, air handler, and filters.


Furnaces are indoor units that burn fuel, like gas or propane, to heat up the air, then distribute it through ductwork in your home.

Fan coils

Fan coils are indoor units that move air over the coil, heat or cool it depending on the weather and season, then distribute it through ductwork in your home.

Ductless vs. Ducted Systems

Split-system HVAC can be ducted or ductless. Ducted split systems use ductwork to circulate the warm air generated from your furnace, fan coil, or heat pump, and the cool air generated by your air conditioner, heat pump, or fan coil. Ductless split systems use small air handlers located in specific areas in your home to heat or cool that individual space.