Troubleshoot Your Furnace Ignition when a gas furnace begins making strange noises or it just doesn’t turn on at all there are several things that can be done to troubleshoot the problem. If you have a gas furnace and it seems like the problem is your furnace and not the wiring in the furnace, then the first thing to try is checking the gas valve. If the valve doesn’t seem to be properly connected to the furnace, then either remove it or have a licensed gas fitter come and reinstall it for you.
the gas valve
If the problem with the furnace is with the gas valve then you are going to have to check the control valve for leaks. Sometimes the gas valve becomes clogged with hair, dust, or other build-ups. This in turn causes the valve to not seal properly with the gasket and prevent it from working properly. To check the gas valve, turn the furnace completely off and unplug it. Pull out the gas valve and check to see if there is a problem. You may need to have it re-threaded or have the gas valve re-inserted with an adapter so it will work properly.
the flue gaskets on the combustion chambers
Another cause of furnace ignition is the flue gaskets on the combustion chambers inside the furnace. These gaskets can crack and rupture and cause a complete furnace failure, which is what we call a blue fire. If you have any doubt whether the problem is with the flue gasket or the furnace itself, you should call an authorized repair technician to determine the cause.
the burner tube and pilot light
Another cause of furnace ignition is the burner tube and pilot light. When the burners are open, moisture can start to collect inside the tubes and cause the pilot light to ignite. Once the flame goes out, this causes the gas to escape from the furnace. So, this is another possible cause for furnace ignition. It’s very important that you never turn your furnace on or off while it is running. Always unplug it first and then shut it off safely.
furnace malfunction is a faulty control circuit board
The third possible cause of an electric arc furnace malfunction is a faulty control circuit board. This is usually a safety device built into the furnace itself. Unfortunately, sometimes the control board fails to do its job correctly and allows the electric arc to travel from side to side within the furnace. When this happens the arc can actually damage parts of your furnace like the combustion chamber.
check for possible electrical shorts
If all else fails and you are still experiencing issues, you should check for possible electrical shorts. Shorting out your furnace can cause extreme damage. If it’s not hot, then you may not be shorted out at all. If the problem is actually the air being blown around inside the furnace, then you need to take your furnace to a repair shop and have it checked out. They’ll be able to give you some advice on what to do next.