CSST with Flare Fittings.

[Richard Mobley]

I found some very interesting gas plumbing. CSST with Flare Fittings. The rest of the job looks pretty DIY. TPFE on threaded fitting and the misplaced gas valve give it away.
Does anybody have a clear illustrations of a proper CSST fitting assembly I can use in my report?28941

[Ron Hasil]

With the Big Box stores selling csst to home owners, I foresee a lot of homes having major issues down the road.

28949

[Rich Goeken]

I found some very interesting gas plumbing. CSST with Flare Fittings. The rest of the job looks pretty DIY. TPFE on threaded fitting and the misplaced gas valve give it away.
Does anybody have a clear illustrations of a proper CSST fitting assembly I can use in my report?28941

As I understand it, the CSST should terminate in a stub drip fitting, and then an appliance connector from the drip fitting to the appliance. The Teflon tape is wrong, it should be yellow, or blue pipe dope should have been used, each rated for gas.

Found this pic, can it help you?

[Ron Hasil]

As I understand it, the CSST should terminate in a stub drip fitting, and then an appliance connector from the drip fitting to the appliance. The Teflon tape is wrong, it should be yellow, or blue pipe dope should have been used, each rated for gas.

Found this pic, can it help you?


White PTFE tape is allowed for gas. The colors are just a marketing ploy. The PTFE tape is or a pipe dope is not to seal the threads, it is to lubricate the threads so the pipe can be fully threaded into the fitting with less friction. Before PTFE tapes and pipe dope, us plumbers used to use a beeswax based grease (before my time).

I hope you noticed I am not calling the PTFE tape Teflon, Teflon is a brand name by Du Pont and they never authorized any manufacture of pipe tape to use the name Teflon. Teflon tape? It's not what you may think. | DuPont? Teflon® (http://www2.dupont.com/Teflon_Industrial/en_US/teflon_tape.html)

[Rich Goeken]

White PTFE tape is allowed for gas. The colors are just a marketing ploy. The PTFE tape is or a pipe dope is not to seal the threads, it is to lubricate the threads so the pipe can be fully threaded into the fitting with less friction. Before PTFE tapes and pipe dope, us plumbers used to use a beeswax based grease (before my time).

You are right, none of the materials are designed to seal, but assist in the installation of the pipe by providing lubrication. Around here some inspectors look for yellow tape or blue pipe dope. Otherwise a discussion develops---right or wrong. They them happy by using the colors.


I hope you noticed I am not calling the PTFE tape Teflon, Teflon is a brand name by Du Pont and they never authorized any manufacture of pipe tape to use the name Teflon. Teflon tape? It's not what you may think. | DuPont? Teflon® (http://www2.dupont.com/Teflon_Industrial/en_US/teflon_tape.html)

It's like Xerox. When Xerox was big in copying it was easier to say "Xerox this" in place of "would you copy this.." Based upon what I see on the Internet listed as "Teflon Tape"---Dupont has a lot of chasing around to do. :D

[Jerome Schrenker]

Notice the unprotected NM cable.

[Ron Hasil]

You are right, none of the materials are designed to seal, but assist in the installation of the pipe by providing lubrication. Around here some inspectors look for yellow tape or blue pipe dope. Otherwise a discussion develops---right or wrong. They them happy by using the colors.



It's like Xerox. When Xerox was big in copying it was easier to say "Xerox this" in place of "would you copy this.." Based upon what I see on the Internet listed as "Teflon Tape"---Dupont has a lot of chasing around to do. :D

Depending on what blue dope they are looking for. For example, there is a brand that actually seals the threads kind of like LocTite. A real bear to take apart when it dries. Then there is Mega-lock, which is just like the white La-co pipe dope, just with a blue tint.

Inspectors around here would prefer us plumbers use a pipe dope that does not have oils in it that give off a flammable vapor, that the gas leak detectors pick up. La-co and Mega-lock will set of a flammable vapor detector. Rector-Seal, a yellowish tan tint to it does not set of the detector. There is a brand that dries hard and seals the threads, but yet is still flexible enough to not break under extreme vibration, the ones I use come in a dark blue, or a bright yellow depending on fluid temperatures.

My point is you can not say for sure when you see one color of pipe tape or pipe dope if it does or doesn't meet the code. That is why when I get my jobs inspected I leave out the cans of chemicals used on the job. Be it PVC primer, cement, pipe dope, solder, flux or anything else that the code dictates.

[Rich Goeken]

......That is why when I get my jobs inspected I leave out the cans of chemicals used on the job. Be it PVC primer, cement, pipe dope, solder, flux or anything else that the code dictates.

Good idea. Some plumbers, and HVAC folks around here do the same thing. Especially if the PVC primer is clear and not purple.

[Mike Clarke]

I prefer to only use the tape for gas specific non tapper gas connection when allowed, for all black pipe (tapered connections) and many other connections I still prefer the pipe dope for gas and for me has been more reliable.

And I never have and never will use CSST as a primary trunk, only use flex for some appliances connections.

As for the tape, I have heard that the yellow is specially formulated but have not research so not sure about that one, anyone know for sure ?

There is a difference, but the only one I know of is the the thickness.
Here is what I found so far.

White PTFE is single density, yellow is double density and pink is triple density.

White – used on NPT threads up to 3/8 inch
Yellow – used on NPT threads 1/2 inch to 2 inch, often labeled "gas tape"
Pink – used on NPT threads 1/2 inch to 2 inch
Green – oil-free PTFE used on oxygen lines and some specific medical gasses
Copper – contains copper granules and is certified as a thread lubricant but not a sealer

as for using the yellow on gas, I read somewhere else that using it has more to do with proper thread lubrication and spark hazards? not sure? also maybe designed to resist petroleum degradation, would like to find a reference if actually a different formulation than just being thicker.

Also reading elsewhere, double density PTFE tape when first introduced was white so could be some of these older installations may be correct using white, would be hard to tell for sure.
The older white thicker tape, I had read that was white and only marketed to professionals and at some point many gas codes were amended to require the use of double density tape for gas connections. And at some point later then the requirement to standardize this as yellow ?

Although pipe dope and tape are supposed to be a lubricant and not provide sealing action, I do know from experience that tapper pipe threads will not always provide a complete seal and pipe dope does help seal in those cases, better than tape in most cases for me.

Anyone have any more specific information on the yellow tape?

Thanks.

[Darren Miller]

Good idea. Some plumbers, and HVAC folks around here do the same thing. Especially if the PVC primer is clear and not purple.

Section 4.2.14 of the National Standard Plumbing code states 'An approved purple color primer' shall be used for PVC or 'an approved colored primer not orange in color' for CPVC.