Unreliable furnace pilot lights are a major issue during cold winter months when you need your heating system to be at its most dependable. It’s a distressing problem that may have you automatically reaching for the phone to call a contractor for help, but unless your system is under a generous warranty, it pays to check pilot light for possible issues first. You may even be able to solve the problem on your own.
There are a few common issues that cause furnace pilot lights to extinguish on their own. Many of them have to do with the thermocouple, a copper coil designed to sense heat from the pilot light. While this seems like a finicky piece of equipment in this context, the thermocouple is actually an essential safety feature. When it can’t sense heat from the pilot light, it shuts off the gas supply to your system, stopping a dangerous gas leak in its tracks.
The flip side, of course, is that problems with the thermocouple often translate into problems with a flaky pilot light. This list covers some of the most easily identifiable symptoms of specific issues with the pilot light itself or the thermocouple:
- Weak flame with dirty surroundings: Pilot lights should burn strong and blue. Weak flames in the orange, yellow or red range typically mean that the pilot light orifice is dirty and can’t sustain a strong flame. This weak flame produces insufficient heat, causing the thermocouple to shut off gas supply and extinguish the pilot light flame.
- Drafty conditions around the furnace: Just like the flame on a birthday candle, a gas pilot light flame can extinguish in a sharp gust of wind. If you can feel a breeze while you’re checking your furnace, this could be the source of your problem
- Dirt and debris on the thermocouple: If the thermocouple or any other part of the pilot light assembly looks grimy or dirty, that can cause problems with the thermocouple’s ability to sense heat or interfere with the orifice.
Your gas supply, whether it comes from a tank or a utility line, could also be to blame. Look out for these symptoms:
- Weak flame with no visible dirt: If your pilot light won’t stay lit and produces only a weak flame with no visible symptoms of problems around the orifice, you could have a gas supply issue.
- Pilot light won’t relight: This occurs when a sputtering pilot light refuses to ignite when you follow the proper steps for your furnace.
Do You Need Professional Assistance to fix Pilot Light?
Some of the above issues are easy to fix even without expert knowledge. For example, if your thermocouple is dusty or dirty, you can shut down your furnace and give the thermocouple a gentle wipe to remove the debris, taking care not to let any of the debris fall down into the pilot light orifice. If your furnace feeds from a propane tank with a shutoff valve that’s not fully open, you can adjust that yourself.
In most other cases, though, it’s best to call a professional to fix your issue. If you can’t identify your issue based on the above criteria, call Northeast Mechanical. The issue could relate to downdraft issues and other problems that are difficult to identify with an untrained eye. Some of these repairs can also be risky, especially if they deal with the gas supply. Gas is dangerous, and messing with gas lines can cause much bigger problems than an unreliable pilot light. When in doubt, don’t hesitate to call for assistance.