Summer is over and winter is close on its heels. So it is time to start thinking of making sure your home’s furnace heating system is ready to keep your family comfortable. High efficiency furnaces with automatic ignition of the burner are becoming more and more common. But what if you still have an older model furnace with a standing pilot flame and you need to light it for the heating season, or re-light it for some reason? We’re going to give you the steps to do so properly and safely!
The standing pilot flame in a gas furnace is a flame that is always burning, sometimes called a pilot light, and serves as an ignition flame for the furnace’s main gas burner. It is an important part of the operation, so if it goes out the furnace can’t operate. This standing pilot flame and its partner the thermocouple make or break your furnace’s operation, so let us explain briefly how they work.
If the standing flame can be called the pilot, then the thermocouple could be considered the co-pilot. It is an electronic device that senses if the pilot flame is present or not. If the thermocouple “sees” the flame, then it keeps the valve to the pilot light open, and allows the main gas valve to open when it is time to fire up the furnace. However if the thermocouple does not sense enough heat from the pilot flame then it shuts down the gas valve.
So has your pilot gone out? It is a common problem, but don’t worry, it isn’t that difficult to re-light it. The steps involved may be slightly different depending on the model of your furnace and the type of pilot gas valve body assembly it has. So the first tip is to try to find the instructions for your specific furnace (check inside the cover panel, or in the instruction manual).
Two of the most common types of pilot valves are one with a red reset button, or one with gas valve knob that can be depressed. There are other less common configurations, but the following procedure is basically the same for all of them.
- Turn your thermostat to the “Heat” mode, and set the temperature all the way up so it will demand heat.
- Open the furnace and find the pilot gas valve. Look for the gas cock or valve knob that is normally labeled “On”, “Pilot”, and “Off”.
- Turn this to “Off” and wait about 3 minutes. This allows time for any residual gas to dissipate before lighting any flame. (NOTE: This is a very, VERY important step!)
- Find the pilot burner, located near the main gas burner tube in the furnace.
- Get your match or lighter ready. Since the pilot is usually hard to reach we recommend using either a BBQ grill lighter, or a long fireplace match.
- Turn the knob you found in Step 2 to “Pilot”.
- Place your lit match or ignited lighter tip at the pilot and push down knob or button. The pilot should light within seconds.
- Keep the knob or button depressed for about 30 seconds. This keeps gas flowing to the pilot giving time for the thermocouple to sense the flame and keep the valve open.
- Let go of the button or knob, and then turn it to the “On” position. This allows the main gas valve to open and ignite the furnace burners.
So there you go! You just lit your own gas furnace pilot light. Now you can turn the thermostat setting to where you usually have it and it will turn the furnace on and off as needed to keep you comfortable.
If the pilot is having trouble staying lit, or fails to ignite there are a number of reasons why, but we recommend calling your trusted heating service company to find out what is the problem. You may also consider converting your standing pilot to an automatically lighting pilot. If you have any questions along this line please don’t hesitate to contact the friendly staff of CMR Heating & Air.
