Plumbing Union ? (a bit apprehensive. safe to use ?

Old 01-27-07, 03:27 PM
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Plumbing Union ? (a bit apprehensive. safe to use ?


Have done a fair amount of home plumbing type of work, but, surprisingly, have never had need to use a "union".

Have to run a line from a washing machine water outlet to the machine, and for various reasons, before I get to the hose itself, I could use a Union in the rigid section to provide some angularity adjustment, as well as the removable advantage they provide.

Have looked at them at HD, and frankly they make me very nervous.

What's your experience with these things.

Once you snug them up, do they tend to stay that way ?

Reason i'm asking is that there is no elasticity in the union coupling itself, so it seems to me that if the threads back off, even a very small amount, there will be leakage thru the ground and polished seat where the two pieces actually come together.

Any thoughts on this ?
Safe to use ? Proven in practice pretty well ?

Are there any other types, or brands, besides the HD ones that are perhaps of better quality ?

Old 01-27-07, 11:49 PM
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Just had a new system installed. Had 4 leaks... guess what they all were. Yup, 4 unions... and do you know what else? all I had to do was get a couple of wrenches and make it a bit tighter. They work... but watch them!!! And keep them accessible!
Old 01-28-07, 06:09 AM
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Once they're tightened and leak free then you should be fine. Like Who said it would be best to keep them accessible.
Old 01-28-07, 06:31 AM
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ground joint unions

why not just use a standard threaded coupling instead? unions are generally used to join two existing pipe runs together. one could also use a l/r threaded coupling with a l/r nipple.

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