What it is:
Central heating systems have a primary heating appliance, such as a furnace or boiler, usually located in your basement, attic or garage. All furnaces have 2 main components:
1. Burners that deliver and burn fuel, heat exchangersand a flue to exhaust gasesous by-products. Or electric elements that produce heat.
2. A blower.
(A cooling radiator type coil may be attached to the heating appliance which is activated in with the outdoor condensing unit. for the cooling season.)
Basic Furnace Operation
1. The thermostat sends a signal to the control board to start the furnace.
2. The conrol board takes control of the furnace operations from now on.
3. The inducer motor turns on.
4. The pressure switch checks and monitors inducer motor speed.
5. The ignitor turns on.
6.The gas valve opens and sends gas to the burners which are lit by the ignitor.
7. The flame sensor proves that the burners are lit.
8. The ignitor goes off.
9. The burners heat the heat exchanger and the temperature is monitored by the limit(s) control.
10. The blower turns on and the temperature is montitered by the fan control(s).
10.a The limit contorl(s) turns the burners off & on to control the inside heat exchanger temperature .
10b. The fan control(s) turns the blower off & on to control the outside heat exchanger temperature.
11. The conrtol board continues to montior the furnace controls to heat the house.
12.The thermostat turns off the furnace control board when the house temperature is reached.
13. The inducer motor runs until all gas fumes are out of the heat exchanger.
14. The after a few minutes the inducer motor then turns off.