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Bruce Ramsey
08-12-2009, 01:23 PM
10 year old property. CSST feeds to attic, T-fitting with one leg to gas furnance and other to gas water heater.

Is iron T-fitting acceptable to junction CSST?

The radius of the bends looks a little severe.

I have some concern about size of pipe to feed two appliances.

What say you?

Bob Harper
08-12-2009, 01:45 PM
Looks like Wardflex brand but you'd need to identify the brand to get the mfrs. specs.

In general, such a transition should be properly supported. It is ok to use black iron fittings in conjunction with CSST but such joints should have support (better than two crummy nails). There might be a concern about strain at the connection if this was located where someone could reasonably be expected to trip over it.

The bending radius for most 1/2" CSST is about the radius of a soft Philly pretzel. You must come here to recalibrate annually....

Yes, there is room enough for concern about sizing both for the riser feeding them and each branch to the individual appliances esp. if this is NG. You would need the input btu/hr rating of each appliance, the run from this tee to the appliances and the run from the meter to this tee.
HTH,
Bob

Jerry Peck
08-12-2009, 02:05 PM
That tee would have worked better had it been laid down flat on the wood.

As installed in the photo the CSST coming out the top of the tee is crimping itself down under its own weight and those who step on it, lean on it, bump it. The upper CSST needs to be secured and supported to take the weight off the fitting connection and maintain a proper bending radius.

Bruce Ramsey
08-12-2009, 03:01 PM
Thanks for opinions.

Interesting transaction. Buyers agent calls and asks if I am available in the next couple of days. She just submitted an offer. Says she will call back to set specific date. Couple days go by. Call her back. Buyer submitted 4 offers, all fell through.

Buyers agent finds a new property. If turns out the buyers agent is also the seller. So she is the buying agent, listing agent and seller. Her husband is a builder and he built the property 10 years ago!

When she does call back she says, "I already convinced the buyer that you are the HI to hire. You are my picky inspector and now you are inspecting my property." :D Just gotta love karma.

wayne soper
08-12-2009, 03:27 PM
manufacturer specs also indicate the need for wrapping the plastice ends to insure no metal cable is visible as well as bonding the manifold to ground. That may be considered the manifold if that's the only hard pipe on the system.

Jerry Peck
08-12-2009, 04:07 PM
manufacturer specs also indicate the need for wrapping the plastice ends to insure no metal cable is visible ...


They do?

I must have missed that in the past. Would you post that information?

Bob Harper
08-12-2009, 05:23 PM
Sure they make CSST tees or you can use black iron. See article 2.1.4 in the Wardflex installation instructions.

You can use black iron because the other end of a straight mechanical coupling is NPT, which is to iron pipe. Most CSST mfrs. sell these manifolds of 3-6 snouts coming off a one piece casting. They are neat as you can run a larger diameter feed or smaller diameter feed to a shutoff, sed. trap, 2psi -wci regulator followed by another trap into the manifold then branch off to each appliance much like an electrical dist. panel. What's really nice is putting a shutoff at each takeoff on the manifold so its you one stop shopping to shut off gas. You write on the yellow polyester jacket which appliance each is serving.

Fritz, most CSST I'm aware of do not *require* the polyester jacket to be kep intact right into the mech. coupling. Gastite does make their coupling with sufficient clearance to do this and encourage it but don't require it. Trac Pipe does not have the clearance so you have to trim it just shy of the coupling. I don't see any reason to wrap it as what is the hazard you are protecting it from at that point if its only an inch or two? In fact, when you route CSST into fireplaces, you MUST remove the jacket since it is technically a 'combustible'.

All CSST must be bonded where it ties into the main gas riser. I haven't see where intermediate breaks in the CSST require secondary bonding esp. all the way back to the dist. panel.

wayne soper
08-12-2009, 05:27 PM
section 4.0 step 5
http://www.gastite.com/include/languages/english/downloads/pdfs/DIGuide2008.pdf

Bruce King
08-12-2009, 07:53 PM
The black csst called counterstrike must have the sheathing up close to the fittings to maintain the "energy dissipation" quality of the pipe that allows (for now anyway) no additional bonding requirements that yellow csst needs. Google counterstrike csst if you need the exact wording from the installation manual.

Jerry Peck
08-12-2009, 08:06 PM
From TracPipe:


Any portions of exposed stainless steel behind the fitting nut shall be wrapped with self-bonding silicone tape TracPipe P/N FGP-915-10H-12, (25 mm wide), or FGP-915-20H12PO, (50 mm wide). This will reduce the possibility of later corrosive attack.

As I recall, that did not used to be in there years ago. Good to know.

Thank you, Wayne.