Water Heaters · Gas Components
Flue Pipe
The metal pipe that vents combustion gases from gas water heaters to the exterior. Typically 3" or 4" diameter, made of galvanized steel or aluminum. Must be properly sized, sloped upward, and securely connected to prevent dangerous gas accumulation. Required for atmospheric vent water heaters.
Common uses
Venting combustion gases, ensuring safe operation, code compliance
Common symptoms
- Poor draft
- Backdrafting
- Corrosion
- Loose connections
Common repairs
- Pipe replacement
- Connection tightening
- Flue cleaning
- Draft improvement
Related terms
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