Help with leaking union

[Sawyer]

I did not have a leak when I started up the Garn. Now 7 months later I have a 1-1/4" brass union at the HX that drips 3 quarts a week. I tried tightening but am afraid to tighten anymore. I have the feeling I will strip the threads with the 15" Crescent wrench if I crank it any more.

Any suggestions on a fix? Pipe dope and re-tighten? Crank the wrench till I can't any more? I would rather try a suggestion than remove and sweat a new one in place. Fortunately I followed the forum advice and installed isolation valves on the HX so I can remove without a big problem.

 

[Willman]

Usually a mis aligned union will leak. Make certain it is perfectly aligned before it is tightened, if not you will have to do whatever it takes to align. If it is lined up perfect then try the loctite thread sealant.

Will

 

[Sawyer]

Thanks Will, I will check the alignment (also the mating surfaces), perhaps something settled and it did go out of alignment, thus starting to leak now. I do have most of my second roll of Loctite 55 handy and will give that a try. It is dripping out the threaded side of the union.

 

[hemlock]

You didn't use sealant on the "hex" threads did you? They do not require it, and especialy if you used tape, that would cause a leak.

 

[Sawyer]

You didn't use sealant on the "hex" threads did you? They do not require it, and especialy if you used tape, that would cause a leak.

Ooooops, I did use Loctite 55 on the HX threads but those are not leaking. I am leaking at a union on boiler return side.

BTW, I sure do like my 262XP, runs like new! Heated handles feel good at zero degrees.

 

[woodsmaster]

The mating surface of the union should seal and there is no need for tape or sealant on the threads of the union except where it is joining to the pipe. I'd try tighting more and if that dont work take it apart and make sure it is allined and there is nothing on the mating surface. I doubt your going to strip the threads with a 15 inch wrench unless you are superman or the incredible haulk. I'd try a pipe wrench with a cheater bar if you don't have a large pipe wrench. J.T.

 

[Sawyer]

"I doubt your going to strip the threads with a 15 inch wrench unless you are superman or the incredible haulk."

Neither ;-)

 

[hemlock]

The mating surface of the union should seal and there is no need for tape or sealant on the threads of the union except where it is joining to the pipe. I'd try tighting more and if that dont work take it apart and make sure it is allined and there is nothing on the mating surface. I doubt your going to strip the threads with a 15 inch wrench unless you are superman or the incredible haulk. I'd try a pipe wrench with a cheater bar if you don't have a large pipe wrench. J.T.

Give that a try. Just make sure you use two wrenches, one to "counter" the torque of the other.
Yeah - the 262xp is a great saw. Mines an oldie, but still runs like new. Needed a new ring this year.

 

[bpirger]

I never had good experiences with unions...they always seemed to leak for me. After they are opened once or twice, never seemed to seal again. When I put in my Garn, I didn't use them anywhere, but made sure to leave a good length of 1.25" copper everywhere I might need to cut something out and couple it back together with sweating. I'm no plumber or HVAC guy though....but never seemed to get them to be leak free. Not sure this is at all helpful, just my experience.

 

[ewdudley]

I did not have a leak when I started up the Garn. Now 7 months later I have a 1-1/4" brass union at the HX that drips 3 quarts a week. I tried tightening but am afraid to tighten anymore. I have the feeling I will strip the threads with the 15" Crescent wrench if I crank it any more.

Any suggestions on a fix? Pipe dope and re-tighten? Crank the wrench till I can't any more? I would rather try a suggestion than remove and sweat a new one in place. Fortunately I followed the forum advice and installed isolation valves on the HX so I can remove without a big problem.

No expert here, but from my experience some things that have worked:

Be sure there's no errant solder on the faces, else heat up and wipe clean with fluxed rag.

Get a new union and some lapping compound and lap the faces using each half of the new union as a lapping tool.

Apply a smearing of Permatex pipe thread sealant (the black organic variety, not the white Teflon stuff) or plain old Permatex Form-A-Gasket to the faces (not the threads). Perfect alignment should not be absolutely critical, one of the main functions of a union is to accommodate a certain degree of misalignment.

--ewd

 

[pybyr]

Perfect alignment should not be absolutely critical, one of the main functions of a union is to accommodate a certain degree of misalignment.

--ewd

An increasing proportion of metal plumbing fittings seem to be made in places that seem driven solely by cost, and from what I have seen, on worn or badly operated tooling-- to the point that I have noticed that getting a good connection (whether by threads, solder, union) is much less of a given than it might have been ten or twenty years ago

 

[Sawyer]

The leak is gone!

I opened the connection, checked the fitting and both sides seemed to be in good condition. I loosened the pipe hanger, applied anti-seize compound to the thread, and reconnected the union. No leak!

It was probably a simple alignment issue. The anti-seize compound seemed to make tightening smooth and consistent.

Thanks for the advice. ;-)

 

[velvetfoot]

Could it be you also tightened it more with the anti-seize on the threads?

 

[Sawyer]

Could it be you also tightened it more with the anti-seize on the threads?

That is definitely a possibility.

 

[velvetfoot]

I didn't use the anti-seize, but a I a very similar experience, only with a smaller brass union. Kept tightening with two big Crescents 'til it stopped leaking. Nervewracking.