1" too small, 1.25" too big

ILikeSteamHeat

Hi all,



This is a great site!  I'm at my wit's end and I'm hoping someone can help an amateur in need.  I need to move a one pipe steam radiator six inches for a room renovation.  My problem is that I can not find a pipe size which will match the union on the radiator.  I'm sure the valve is 1 1/4 inch because I happened to have a 1 1/4 coupling which will fit onto the threads on the valve.  When I try to attach a 1 1/4 pipe to the union, the union will begin to thread on but does not even come close to threading on enough to seat the nipple into the pipe.  The frustrating thing is that the very same pipe will thread into the coupling, which fits onto the valve. 



I can't help but think that I'm missing something fundamental here.  Any help would be greatly appreciated.  Thanks in advance.



Tom

STEVE PAUL_3

TRY THIS

Instead.

Remove the union spud from the radiator tapping, screw the spud with the union collar into an 11/4" pipe coupling and fill in the space between the radiator and the coupling with the proper size nipple.

The union thread is not a NPT (pipe) size thread and will not tighten up correctly.

Jamie Hall

Ah yes, threads...

and unions.  Union nuts, such as the one which is captive to the radiator spud, have a different thread than a pipe.  The valve has proper union threads on that end of it and, if you notice, the machined union ending.  Two solutions.  If you can, take the valve off the pipe, attach it to the radiator, then use a nipple or something to get to the pipe.  Or use two unions...

icesailor

Just right:

Wouldn't it be easier to get a radiator spud/union wrench and unscrew the union nipple from the radiator, use the coupling and the nipple. Then, no MM connection.

It's just a (thing) to get it out. Big crescent wrench and jump up and down on it.

Whatever you do, don't screw up the union or valve/ell. Getting THAT out is really a job. In fact, as I consider myself a "pro", I have to psych myself up to do things like this. So great is the chance of a disaster

ILikeSteamHeat

Thanks!!!

Wow.  Thanks for the responses.  As much as I don't want to try and get the spud out, I think that's the best way.  I think the fewer connections I have, the better.



Anybody know a good doctor that can put my internal organs back in.  I'm sure I'll hurt something. 

Charlie from wmass

So where are you?

I am going to guess the valve is 1" if that coupling threaded on to the union threads.Great thing about working on steam systems is the second chance to do things properly. Doctors seldom have that luxury.

Gordan

Depends on what's broken. :-)

A bone, well, they just break that again and re-set it!

ILikeSteamHeat

Valve is 1 1/4

Actually the pipe is one inch and the valve is an inch and a quarter.  There's a bushing between the pipe and the valve.  I have a 1 inch pipe that is too small for the union nut and a 1.25 inch pipe that is too big.  It starts to thread on but then stops after half or three quarters turn.



I have replaced valves in other rooms they are all one inch.