We bought a used gas dryer and it came with a flex gas line. Hooked
everything up and we smelled gas. Called the gas company and they came out
and identified the problem as a leak in middle of the flex line. While
there, he had his sniffer out and said we had a slight leak on the water
heater gas supply line. He put some wrap on it and said it would be fine
until it was tightened up.
I'm stumped how to do that. ½ black pipe runs down to a T and the leak is
in the center of the T that supplies gas to the water heater. There is a
shutoff and union in the line. Other side of the T drops down with a 3"
nipple and is capped. There is about a 6" run from the center of the T to
the water heater.
If I open the union and begin to tighten the line into the T, at the same
time I'm tightening at the T, I'll be loosening the line that runs to the
water heater. If I try and rotate the T, I'll be rotating it away from the
supply line and it won't reconnect, unless I managed to get 1 full turn
The gas company guy said it just needed tightening. I'm thinking that
actually means I need to completely disassemble this from the union down,
clean all the parts up and start over with new pipe dope and reassemble from
the heater back to the union. Or am I missing an easy fix?
No, you're right. You have to back down from the union. And that
nipple on the T needs to point down. It's a trap sort of thing. There
is teflon tape for gas now if you prefer that. It comes in a yellow
roll. Not supposed to use the regular stuff but beats me why.
That's it... :)
Actually, there's one side benefit of the thicker film that can be
significant on gas. It doesn't tend to shred so badly into those tiny
little threads that if you ever get one inside a gas line can plug
Yep (and nope)... :)
Check on condition of the pieces, of course, before reusing.
Is the leak confirmed at a threaded joint not a pinhole failure in the
body of the tee or similar?
There is a water trap somewhere in the line I presume? Be good time to
clean it out if so, or install one if not.
I think it depends on exactly where the leak is.
When you say the leak is in the center of the T, do you mean the leak is
where the threads of the T meet the short horizontal pipe that goes to the
hot water heater?
If so, I would say to do this:
1) Shut off the valve.
2) Loosen and disconnect the Union joint.
3) Loosen and take off the vertical short piece that comes out of the bottom
of the T.
4) Loosen and take off the vertical pipe that comes out of the top of the T.
5) Loosen and take off the T from the short horizontal piece that goes to
the hot water heater.
6) Use gas pipe thread sealant or yellow gas pipe thread sealing tape and
re-attach the T to the short horizontal piece that goes to the hot water
7) Use gas pipe thread sealant or yellow gas pipe thread sealing tape and
re-attach and tighten the vertical bottom pipe and vertical top pipe.
8) Re-connect and tighten the union.
9) Open the valve.
10) check for leaks by smell and/or soapy water around the joints.
If the leak is where I suggested above, the T probably only needs to be
tightened by 1/2 turn to seal the joint, but it's better to disconnect it
all and re-do the joints with new sealant or tape in my opinion.
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