Troubleshoot a Gas Furnace Repair

Before one understands the furnace repair process, it's important to understand the different functions of a furnace and how they operate. The gas furnace is an appliance looking like a large box that does the following:

  1. Takes in cold air
  2. Cleans it with an air filter
  3. Heats it up with a gas burner using a stainless steel heat exchanger
  4. Distributes the warm air with a blower motor through your home's ductwork

The heated air then cools down in the various rooms and returns to the furnace through return air grills and ductwork. The cold returning air enters back through the air filter into the furnace to complete another heating loop.

Sometimes there is a humidifier mounted on the furnace or the return air ductwork.

Furnaces come in different efficiencies measured in AFUE (annual fuel utilization efficiency).

Once in a while things don't work quite right and you need to troubleshoot a gas furnace repair or relight a standing pilot if it has one. Most newer furnaces have electronic ignitions and need special troubleshooting.

Let's take a look at the more common problems and furnace repairs you may have to make.