Video Guide for what makes a forced air split central system for heating and air conditioning work. A split central system consists of indoor equipment that includes a gas fired furnace or air handler, and outdoor equipment consisting of a condensing unit or heat pump. They are connected by a pipe called a line set.

The gas fired furnace produces a flame that heats up a wire grid (heat exchanger). The blower blows this air through duct work in the house that comes out outlets to be drawn across the house through a larger duct known as the air return. The air return circulates air across the room, keeping it comfortable, and then returns back to the gas fired furnace where the process repeats.

There are 3 styles of burners: 1 Stage, which just turns on and off; 2 Stage, which has a high and low setting; and the most efficient 3 Stage, in which the modulating increases or decreases based on demand.
The blower motor is available as multi-speed (low, medium and high setting) and variable speed, which is more efficient.