New Compression Shut Off Valve for Toilet Leaking - DIY Chatroom

C_J_GO · 10-16-2009, 08:39 PM

I am installing a new toilet in a new bathroom and I bought a compression type fitting/valve to install on the copper stub out of my wall. I have now installed 2 valve, both of which leak from the valve. Water is coming out of the compression nut on the wall side of the valve. I assume the compression ferrel is not tight enough. I have turned it per the directions, but do not want to go too much more in fear of overtightening it. One question is that I thread taped the threads on the valve; would that cause the compression nut not to compress the ferrel as it should? I do not want to try anything more until I hear back on some advice.

Thanks

C_J_GO · 10-16-2009, 08:41 PM

A little more info...
My first valve I installed leaked and I kept tightening the nut down, eventually tightening it too much as when I removed the valve, the ferrel was indented into the copper pipe. Thus I have not tightened the second as much. I cut off the back section of copper pipe before installing the second valve, but I do not have much more I can cut off. Suggestions?

rselectric1 · 10-16-2009, 08:45 PM

Until the plumbers can get to your question for a more definite answer, it has always been my understanding that putting teflon tape on a compression fitting can actually cause it to leak.

I have found that sometimes you have to give it pretty good torque to get them on correctly, but let's see what the pro's say.

Plumber101 · 10-16-2009, 08:54 PM

Tape is not required for compression fittings

Clean off the tape and try again

JDC · 10-17-2009, 08:57 AM

Agreed. Get rid of the tape. When I have a stubborn one I'll put a light coating of pipe dope on the ferrule, but even that isnt required. The ferrule makes the seal, not the threads.

SULTINI · 10-18-2009, 10:15 AM

Same as everybody else remove all tape. Sometimes I put a little veg oil on my finger and run it around the copper and ferrule then tighten it, watch out you don't over tighten a common mistake, tighter is not always better in this circumstance.
Make it snug turn water on slow watch for leaks tighten little more if leak present.

C_J_GO · 10-22-2009, 05:30 PM

Yep, got rid of the tape and it has been dry for 2 days now. Thanks for all the help.