For furnaces with a standing pilot light, few things are more frustrating than relighting it, only to have it go out again shortly after. Old Glory Air Conditioning and Heating explains the most common reasons behind this recurring issue.
The thermocouple is a safety device designed to detect whether the pilot flame is lit, shutting off gas flow if it senses the flame has gone out. A worn or faulty thermocouple can incorrectly signal that the flame is out, causing the gas supply, and the pilot light, to shut off even when everything else is functioning normally.
Sometimes the issue isn't the furnace itself, but a draft in the surrounding area blowing out the pilot flame. This can be caused by nearby vents, doors, or other airflow sources affecting the immediate area around the pilot assembly.
Over time, dust and debris can accumulate in the small opening that allows gas to reach the pilot light, restricting proper gas flow and causing an inconsistent or weak flame that struggles to stay lit.
If the gas valve controlling flow to the pilot light is malfunctioning, it may not be providing consistent gas flow, resulting in a pilot light that either won't light at all or won't stay lit once ignited.
Even a properly functioning thermocouple needs to be positioned correctly within the pilot flame to accurately sense that it's lit. If the thermocouple has shifted or bent out of position over time, it may fail to detect the flame properly.
In some cases, inadequate gas pressure reaching the furnace can result in a weak pilot flame that struggles to stay lit, particularly if there are other gas appliances in the home competing for the same gas supply.
While it might be tempting to simply keep relighting the pilot each time it goes out, this approach doesn't address the underlying cause and can become a recurring hassle, or in some cases, indicate a developing safety concern that needs professional attention.
If your pilot light continues to go out despite repeated relighting attempts, or if you notice a yellow or flickering flame rather than a steady blue one, it's time to call for professional heating system repair rather than continuing to troubleshoot on your own.
Our technicians can accurately diagnose why your pilot light won't stay lit and provide the appropriate repair to restore reliable operation to your heating system.
