Why is My Exhaust Pipe Glowing?

The holiday season has finally arrived, and with it comes festive lighting displays inside and outside of homes. Since it is the “season of light,” we thought we’d cover an especially illuminating plumbing topic: what happens if you find a plastic pipe glowing inside your home? 

While it’s a rare phenomenon, direct sunlight can enter a white PVC exhaust pipe and give it a glowing appearance. As long as there are no leaks or other issues, the glow shouldn’t be a cause of concern. 

What does the exhaust fan do?

Appliances such as furnaces, heat pumps, tank water heaters, and tankless water heaters use natural gas as a fuel source. The combustion creates toxic gases that need to be vented outside; otherwise, they could cause a hazardous situation for people and pets within the home. The exhaust pipe runs either horizontally or vertically to release the gases outside. 

Is a glowing vent pipe dangerous?

We completely understand why a homeowner would be worried over the sight of a glowing exhaust pipe. It can happen when direct sunlight creates an illuminating effect inside the white PVC pipe. The pipe needs to be uncovered, and the light has to hit the opening just right. The phenomenon is most likely to appear closer to the roof – such as in an attic – but there are reports of glowing pipes even in basements. 

What to do about a glowing PVC pipe?

When there’s anything unusual with your HVAC or plumbing (especially when it involves natural gas), it’s always best to exercise caution. As long as no strange noises or smells accompany the glowing exhaust pipe, wait to see if the effect changes as the sun moves or goes down. If it does, you shouldn’t be too worried about the light show. To prevent sunlight from getting inside the pipe, you can check to make sure the vent cap isn’t missing and the flashing is in good condition. 

Plumbers serving the Houston area

It’s always better to be safe than sorry, so if you discover any oddities with your plumbing – such as an eerily glowing pipe – don’t hesitate to call Rooter-Man Plumbers. We’re here to help 24/7. Call us today at 281.351.4422.

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