Water Heaters - Compression Fitting leak
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tpyle
05-25-09, 07:18 PM
I just installed a new 40g gas water heater. I bought new compession fittings. The compression fitting on the intake has a slow leak. I put teflon tap on the fitting, but no putty. I have tighten the fitting as tight as I can. What are my options with the last one being call a plumber. Do I need to take off the fitting and re-tape and use plumbers putty? If I do that do I need to drain the tank? Thanks!
blacknbluedog
05-25-09, 07:31 PM
Try reapplyng the tape or try a liquid pipe thread sealant.
furd
05-26-09, 10:59 PM
If you used Teflon tape on the ferrule of a compression fitting then you did it wrong.
NEVER use tape or any other kind of sealant on anything but a tapered pipe thread. The only thing to use on a ferrule is a tiny amount of plumber's grease or a drop of oil to make the nut slip as it is tightened.
By overtightening the ferrule connection you have most likely distorted the ferrule and possibly the copper tube (pipe) also. The only fix is to cut off the ferrule and end of the pipe and start over.
To properly "make up" a compression fitting you have to first have a square end on the pipe and the ferrule must "seat" on a perfectly round area of the pipe. Then insert the pipe until it "bottoms out" in the fitting. Tighten the nut one and one-quarter turns past finger tight with an appropriate adjustable wrench or fixed jaw wrench. Do NOT use pliers or a pipe wrench on compression fittings. If it still leaks slightly you may slightly tighten the nut until it stops leaking up to a maximum of two full turns.
NEVER use tape or any other kind of sealant on anything but a tapered pipe thread. The only thing to use on a ferrule is a tiny amount of plumber's grease or a drop of oil to make the nut slip as it is tightened.
By overtightening the ferrule connection you have most likely distorted the ferrule and possibly the copper tube (pipe) also. The only fix is to cut off the ferrule and end of the pipe and start over.
To properly "make up" a compression fitting you have to first have a square end on the pipe and the ferrule must "seat" on a perfectly round area of the pipe. Then insert the pipe until it "bottoms out" in the fitting. Tighten the nut one and one-quarter turns past finger tight with an appropriate adjustable wrench or fixed jaw wrench. Do NOT use pliers or a pipe wrench on compression fittings. If it still leaks slightly you may slightly tighten the nut until it stops leaking up to a maximum of two full turns.