Bend radius for gas flex line - InspectionNews

Jon mackay · #1 (**permalink**) 05-08-2007, 12:01 PM

Is there a specific bend radius for the yellow gas flex lines.
The one in the picture is pulled real tight and I was going to recommend correction.

Paul Kondzich · #2 (**permalink**) 05-08-2007, 01:41 PM

Sure looks wrong to me.

Dom D'Agostino · #3 (**permalink**) 05-08-2007, 04:07 PM

That looks like Tracpipe.

Here is the Install guide for that product, lots of data here to review.

http://www.omegaflex.com/trac/litlibrary/D&I_Guide.pdf

The minimum radius is listed in the chart, along with other specs:

Bob Harper · #4 (**permalink**) 05-08-2007, 05:46 PM

Ouch! Yes, way too tight of a radius. Always refer to the listed instructions and the Trac Pipe shown is made by Omegaflex, so that is the correct std.

Rule of thumb for most brands of 1/2" CSST is the radius of a soft Philly pretzel. We sell calibrated pretzels up here. Also, calibrated golf balls as they are referred to on the tags on ANSI Z21.24 flexible appliance connectors.

I would recommend this plumber remove the CSST fitting, install an ell to a sediment trap with a tee and the gas line coming off the snout of the tee horizontally. That creates a smooth, straight run for the gas line without bends and the trap to protect the appliance downstream. If this space is outside the thermal envelope, check with your AHJ on cold traps. Also, check the spacing on supports for this CSST. IF there was a union on that black iron of course, the simplest solution would be to rotate that ell to where the gas is going.

Looks like a damp location. What's up with the welded wire and insulation? Rat farm?

HTH

Rick Hurst · #5 (**permalink**) 05-08-2007, 07:02 PM

Jon,

It looks as bad as this one. They were using it as a lighter for the firewood.

Bob Harper · #6 (**permalink**) 05-09-2007, 05:44 AM

Rick, that is not CSST. That is a "flexible appliance connector" and IS listed for gas logs as long as you follow the rules. It is too long. However, log lighter pipes require a black iron pipe penetrating the firebox only--no CSST into log lighters. The black iron not only is more durable but is rigid and cannot be knocked around by logs the way a CSST line would.
Two easy ways to differentiate CSST from flex connectors are the fixed flare nuts on the ends and either stamping on those nuts or in this case a sliding ID ring. Other ways include the shape of the corrugations, the depth of the corrugations, and the lack of markings stating listed to LC1 on the jacket or an EHD (equivalent hydraulic diameter). CSST is usually cut to fit versus standards lengths for flex connectors. CSST also has foot markings like a built in tape rule. CSST has its brand imprinted on the jacket.

Is that a 3/8ths inch copper line I see bunched up behind the grate in this old Majestic Fp? Where does the gas line enter--through a knock out or just drilled through the sides of the box?

HTH

Rick Hurst · #7 (**permalink**) 05-09-2007, 05:52 AM

Bob,

You are correct. I had CSST on the mind from reading the prior post.

Actually, it was aluminum entering through the firebox wall. No hard pipe was present.

Bob Harper · #8 (**permalink**) 05-09-2007, 05:35 PM

Whoa! Aluminum tubing not allowed through the firebox wall!