How does Gas Fired Central Heating work?
There is a range of flames where the gas burns, this is at the bottom of the furnace. Directly above it is a heat exchanger which looks like a lot of tubes - the tubes lead up and out of the house they are the exhaust of the flame to get rid of harmful gasses. the other part of the heat exchanger is open to part of the house and there is a filter above the heat exchanger there is a fan that draws air through the filter up through the heat exchanger and then into Ducts which go all through your House and the heated air is released into all of those rooms. You need to replace the filter periodically as a dirty filter will slow down the airflow and eventually burn out the fan motor.
