Pipe Joint Compound - for gas pipe inside fireplace

[Tidybuoy]

I have to install a new gas burner in the fireplace (simple cast iron starter). I'm wondering if I need to use pipe joint compound and if there is a special kind since this will be in a fireplace exposed to heat. Home Depot said yellow Teflon tape would work but I don't necessarily consider Home Depot to be the experts.

Any advice?

[craigster59]

You could probably use Firestop, either putty or sealant....

https://www.amazon.com/3M-Fire-Barrier-Moldable-Putty/dp/B002FYAMPM/ref=sr_1_3?dchild=1&keywords=firestop+putty&qid=1609277120&sr=8-3

[Bugsinrugs]

Rector Seal or yellow Teflon tape

[unclebilly]

Make sure the putty is rated for gas, some are not. Also, many ‘dopes’ are not recommended for pipes over or under (can’t recall which) a certain nominal diameter.

[fanaudical]

Yes - Need to use something on the threads.

+1 for Rector Seal Yellow (or equivalent) or the yellow PTFE tape.

[Bill Douglas]

I'd be inclined to get a registered gas expert in to do the fitting and testing.

[drcoastline]

Pipe dope on the black pipe leading to the Fire place. The yellow flex line DOES NOT USE any sealants. The included fittings are all you need for a proper seal. When you buy the yellow flex line it will have all the fittings needed to go from the shutoff valve to the burner and the gas leak detector in the package. The fire place is no different than any other gas burner.

[wdfifteen]

Joint compound on iron pipe threads is just there to lubricate the steel-to-steel interference interface so the threads don't pull pieces out of each other as they grind together and distort, making the steel - to - steel seal. Once the pipes are tight the lubricant serves no other purpose. So any good pipe joint compound will work.

[Zeke]

Originally Posted by wdfifteen

Joint compound on iron pipe threads is just there to lubricate the steel-to-steel interference interface so the threads don't pull pieces out of each other as they grind together and distort, making the steel - to - steel seal. Once the pipes are tight the lubricant serves no other purpose. So any good pipe joint compound will work.

Not altogether true. In some instances overcharging the pipe system in testing (15 lbs. for 30 minutes) has blown out the compound. So 50 lbs. is no bueno.

Also the OP confuses. There are hard piped connections as well as the flex lines. Which one is being used? If flex, the only pipe compound used would be the shut off to hard pipe. Usually this joint is far enough out of the heat zone to require any special treatment. Use of the yellow tape is fine.

BTW. the way I read it is that a simple iron pipe with hole drilled is what's being installed and that is hard piped.

If you really want to get down to it, there very well may be info on your AHJ's web page or just the building dept in general.

Lastly, once past the shut off (unless some of the pipe is concealed), who cares? If it leaks inside the fire box it will ignite and you'll know where to reassemble and retighten.

Just kidding.

[Tidybuoy]

This is what I'm installing.

All of the gas plumbing up to the fireplace is already plumbed and includes an on/off valve in the wall. I'm just replacing the unit that sits under the wood rack.

I will use the yellow Teflon tape that is for gas. My primary concern was that the tape would not hold up to the heat.

[Zeke]

Then clean up the threads and install it with the putty. The putty will lube the installation to tight enough.

[NY65912]

+1000 Rectorseal No. 5 We do miles of gas piping and it is all we use, with no issues.