duct taping exhaust pipes

[Uno]

ps I used a different screw for the fastening: a little, metal duct screw.

[AZ Nomad]

Doh! I misread it as an OT automotive question. A furnace isn't going to have the exhaust pressure waves of an internal combustion engine.

[AZ Nomad]

Yes, I usually think of the exhaust of a furnace refered to as a chimney pipe.

[mm]

Okay, I get it.

I used exhaust pipe this time because the OP had in reference to a water heater. and no one quoted had used a different term.

So we agree. Good!

[mm]

That didn't clue me in. I figured maybe some new fancy furnaces do!

[jw]

The original stuff was made for ducts, to be used to keep the pipe seams from leaking on hot air ducts or cold air returns. Most of the stuff sold now at Walmart and hardware stores is just cheap junk. Sure it has many uses, but I would not use it on ducts. I assume the "good stuff" may still be available from heating supply outlets.

[RES]

I think that some trolling has been going on, but in case the question was for real, the answer is: Repair the duct, screw the pieces together. The duct- in fact any duct- should be mechanically sound before any sealing. Duct tape, as used in the trades, is used on some ducts to overlay a seam, but the seam itself must be tight, entirely closed and sound before applying the duct tape. I've seen inspectors use a pick or knife point to test just that issue.

For a vent pipe, this is even more important. Personally, I've never seen a professionally installed water heater, boiler or furnace vent pipe held together, spliced or even reinforced with duct tape. It'll burn, dry out or fail. Possibly the aluminum "tape" could be used, but even that has an adhesive that would probably fail due to the heat.

You're much better off replacing the bad section of the vent, from the draft hood up. The cost isn't that much and you're going to be a lot safer.

Nonny

[DD_BobK]

adhesive that would probably fail due to the heat.