Why does my water heater smells like burnt plastic?

Player

Hi, my water heater has recently, periodically produced a smell of burnt plastic (from the exhaust tube area). I played with the heat temp and the burner turned off. Since then (a week or two ago) I haven't smelled it again...but it concerns me. The water itself doesn't taste or smell funny. Do I need a new water heater?

Just Bill

The only thing I know of in a water heater that might smell like plastic is insulation, and that is normally well packed away from the flame. Pull the bottom cover and check the burner area, it may need cleaning. Rust and debris often drops down and can disrupt the flame. If this is a newer gas heater with explosion proof devices, you can't do any maintenance on the burner.

Player

I'll check, but I think it's an older unit. Looks new, but I know it isn't.