I love DIY and am trying to learn new skills slowly and sensibly. My latest project has involved changing some shut-off valves. One such valve used a compression fitting.
My question is as follows. When is a weeping compression fit a problem? I tightened the compression fitting and it weeps VERY SLOWLY. In a day it may drip perhaps once, perhaps not at all. Often the drip evaporates before it has time to form. I do not want to overtighten the compression, so am living with it in the hope it will just ‘fur up’. Is this sensible?
I did not reuse the compression fitting (it was a new one) and I did clean the pipe. My only oversight was to forget to use teflon tape.
Thanks Brian. I still am unsure whether teflon should be used in a situation like this. On a compression thread it may act as a lubricant rather than a sealant and cause the joint to leak. I usually hand tighten plus a quarter turn.
I coat the compression ferrule with a dap of teflon paste before I tighten everything up. No teflon tape. The paste will fill all of the various nooks between the fitting parts.
One should always check the shutoff cocks for leaks. I wrap a piece of toliet paper around the valve. It will soak up any leaks.
I have found in a new installation that most people over tighten these fittings. I recommend that you do not use teflon tape. Hand tighten and then using a wrench tighten about 1/2 to 5/8 turn to snug up. Then water test. This will allow you if it drips, to tighten until leak quits. This works well on Brass valves and Chrome supply lines. Vynyl supplies use plastic ferrouls, be more careful not to over tighten.
gwilcox
they basicly always leak the first time you turn water back on
re-tighten, check, re-tighten
what you are doing is compressing that ferrel (spelling?)
do not use tape or dope
do use 2 wrenches and be sure to not let copper or tubing bend
I’ve been using pipe dope on these for ten years with no problems. If you read the package on supply valves it will say to use plumbers grease on the ferral.
