Things You'll Need
Tape measure
Cordless drill
Galvanized sheet-metal ductwork
Snips
Pipe crimper
Sheet-metal screws
High-temperature silicone caulk
Caulk gun
Gloves
A furnace flue directs the poisonous products of combustion out of your home. It typically runs from the furnace to a chimney. The gases it exhausts are hot and moisture-laden. Since a furnace flue is made from galvanized ductwork, it corrodes over time once the galvanized coating breaks down. When a furnace flue corrodes, poisonous gases invade your home, so it's best to repair a furnace flue by replacing damaged piping before it corrodes completely.
Step 1
Turn your furnace off. This prevents flue gases from entering your home during the repair.
Video of the Day
Step 2
Remove the damaged flue pipe out of the piping system by pulling each connection apart.
Step 3
Measure the length of the damaged flue pipe and cut a replacement at that measurement. Crimp one end with your pipe crimper.
Step 4
Slide the new piece of flue pipe into place and push the connections back together.
Step 5
Install three to four sheet metal screws at each connection and caulk with high temperature silicone caulk.
Video of the Day