A couple of years ago I had my furnace replaced and the installer
installed the gas cutoff valve for the furnace on the flexible Gas
Appliance Connector rather than on the rigid pipe feeding it. I
objected and made him run additional rigid pipe up to the point at which
the cutoff valve was installed because I saw it as unsafe. Yesterday I
was talking to a plumber who was installing rigid pipe for a gas
connection and mentioned my objection to the gas valve being installed
on flexible connecting pipe. He implied that it was not illegal. The
type of piping I am talking about can be seen at:
I realize there are many new choices for connecting gas that did not
exist years ago, so perhaps he is referring to one of those? My
question is: Is it legal (to code) to put a cutoff valve on flexible
piping such as the link above shows, or must it be on rigid pipe??
It's an interesting question. I think the key to your question may be
what's the definition of "installed on a flexible connecting pipe".
there are several possibilities:
A - It's installed in the middle of a flex line and the valve itself
secured to anything other than the flex pipe.
B - It's on one end of a flex line and the other end of the valve is
connected to rigid pipe.
C - It's installed in the middle of a flex line and the valve is
to a support
From what your furnace guy was going to do sounds like it was
method A. I would not think that would be allowed, but then one
would think that if this was a real HVAC company doing the install,
they would be familiar with the code. If an inspection/permit was
required, then you would think the installers would know what is
or isn't allowed or else it's going to fail.
I would think option C would have to be allowed, because CSST
is used for all kinds of gas piping now, not just for short connection
to an appliance. So, if you have CSST running through a building,
you're going to have to have valves in places.
Hopefully someone will know the actual code.
Originally, the gas valve was attached to rigid pipe and a flex line
(about 2 foot) was run from the gas control valve to the old furnace.
This is how most gas connections are made to things like gas clothes
dryers. When he took out the original furnace, he changed the position
of it in a way that the existing rigid pipe was several (perhaps six)
feet away from the control area of the furnace. (Where the access
panels are) In order to make the connection from the existing rigid
pipe to the new furnace, he removed the cut off valve from the rigid
pipe, attached a flex pipe about 6-8 feet long, attached the cut off
valve to the end of it, and finally ran a 2 foot flex pipe to the
furnace control valve. In other words, the cut off valve was at the end
of a long flex pipe and not directly attached to rigid pipe.
I hope the above clarifies the situation. Of the choices above, I
would say that (A) was probably the best description. I felt
uncomfortable with a flex line that long and felt it was vulnerable with
no way to cut off the gas if it leaked. Perhaps I was overly cautious?
In other words.... he did a hack job / "scab on" because he wanted to
finish in the minimum amount of time.
"He implied that it was not illegal." Of course he did... to support
his poor installation job.
In dependent of whether it was legal or not, how many people would
chose that installation means over piped close & valve securely
The code is the minimum acceptable standard.. the minimum is not
always "best practice".
While I agree it should go before the flex pipe when connecting an
appliance, there is still some purpose to the valve in any case.
It's primary use is to shut off the gas while connecting or
I don't think you were overly cautious. I'd say you have good
sense and the installer did not. Your better description seems
to indicate another problem, which is I don't believe a flexible
pipe like that is permitted to pass through the cabinet
opening of a furnace. The concern being that if it touches the
cabinet, vibration from the furnace could cause the line to fail
over time. Normally, black pipe is used to come out of the
cabinet. Then you have a tee, one end going down and capped
off to form a short stub that is supposed to help prevent any
debris, condensate etc from getting into the furnace. The the
gas valve is usually located right there by the tee, or close by,
again with black pipe.
Was there a permit? Inspection required? You sure would
think that someone doing pro furnace installs would know
what it takes to pass inspection. It ain't that hard. I put my
own furnace in and it passed first time. I used all rigid black
pipe, but the flex stuff is permitted too, at least in most areas.
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