Should I reuse union fittings on steam radiator?

midiman143

Hello everyone I am adding a steam radiator to my sunroom which has all the piping already going to it, just lacks the radiator and the shut-off valve itself. I acquired a radiator the summer and bought all the supplies to make it happen. Started doing my research into this and I've seen some sources that say it's going to leak if you don't use the fitting that came with the new valve but then I watched the video from this old house where he reused it along with enough plumbing dope. It would certainly save me the headache of cutting it out do you guys have any strong opinions? I also would have to modify my Spud wrench to get the new fitting in the radiator because it's hitting some of the hardware in the radiator.

Reference videoes:

Leaving it in: around 6:15 mark https://youtu.be/HNnUO3-fj8Q?si=FiM-lDv4_GBlbgvb

How I would take it out: around 2:00 Mark

https://youtu.be/pSPGLJXypK0?si=un5v9cT_QnUdMl2r

Jamie Hall

There's no harm to trying. Sometimes it will work if you get everything lined up right... sometimes not. Just don't crack the clamp nut. If it won't seal after hand tight plus less than a turn, take it apart again and make sure everything lines up and use dope liberally. Good luck!

Waher

You can't reliably reuse the spud in the radiator with a new valve. Spuds are machined as a pair with valves at the factory and there has never been an industry standard for the mating surfaces. If you try to use a valve with any spud other than the one it left the factory paired with, it is highly unlikely the nut will seal. This Old House is notorious for dubious advice.

Mad Dog_2

Is Rich Threthewey still on TOH?  I remember Bob Vila..
MAD DOG 🐕 

EBEBRATT-Ed

@midiman143

The safe play is to replace the radiator spud. Even if the old one matches and the nut threads on when you tighten it, and they are not matched you could damage the new spud then your screwed.

You can buy a spud removal/install tool but they often don't work on the old spuds #J40030 at Supply House.com

or


Take a hacksaw and cut the nut off the old spud. Make two cuts 180 deg from each other so the nut will split in half. Don't cut the old spud any more than needed. Break the nut after you have most of it cut from both sides Then find some metal like a cold chisel, a large bolt, a pipe nipple etc. that will fit in the hole in the spud. You want to keep the spud from crushing when you put a pipe wrench on it so the snugger the fit the better.

Dan_NJ

https://youtu.be/cJ7jAL3sOCQ?si=rr3GuCvu8oguxLwF

midiman143

@EBEBRATT-Ed thank you for the reply and all the info. Why would you not want the spud to crumble in on itself? all the videos I've seen that's almost exclusively what they do. They make a cut and then cold chisel it till it crumples on itself and then you just take it out

Waher

The crumple method can result in damage to the threads in the radiator and debris getting inside the radiator. You don’t want to have to retap the threads for a spud/bushing and flush out metal debris if you avoid creating that extra work for yourself. Ed’s method is the safest way to do it.

Jamie Hall

Totally agree that the safe play is to remove the old spud. Completely. All I was suggesting is that there is no harm -- provided you don't damage something -- to trying to match the old to the new. Probably a waste of time, but... one gets lucky once in a while.

RTW

I believe you are Massachusetts, so you may want to have Radical Radiator Co. that's north of Boston do the work properly. They have specialized in refurbishing steam radiators for decades - Regards, Bob

midiman143

Thank you everyone for the great input! @RTW you are correct i am just north of Boston maybe I will give them a call.

EBEBRATT-Ed

@midiman143

If you cut the nut off so you can get a wrench on it you have an over 90% chance the spud will come right out and you can easily install the new one.

If the spud goes oval or crushes then you go the sawing and chisel route. You can probably avoid that.

Intplm.

I have given up on trying to unscrew the spud from the radiator.

Why not? Why not try and mate the old with the new? Put some pipe dope on the face of the ground joint and tighten it up. If it doesn't work then you have to go with plan -B-.

When I do try the spud wrench usually doesn't stay in place or you can sometimes get a pipe wrench on it and turn it but how often does that happen? It just warps.
So I just cut the thing out and be done with it.

EBEBRATT-Ed

@Intplm.

I have had pretty good luck removing them. You have to cut the nut off to get enough room for a small pipe wrench with a cheater pipe on it. If you plug the hole so it can't collapse it will usually come out. Of course, when they are all painted up the pipe wrench wants to slip.

ChrisJ

EBEBRATT-Ed said:

@Intplm.

I have had pretty good luck removing them. You have to cut the nut off to get enough room for a small pipe wrench with a cheater pipe on it. If you plug the hole so it can't collapse it will usually come out. Of course, when they are all painted up the pipe wrench wants to slip.

I cut the nut off and then used a 24" wrench on it. Seemed to come off with ease with that method.

midiman143

Hello everyone wanted to update with this success. I used the suggestion of having a piece of metal to prevent the egging AKA used another wrench help to make it possible but I couldn't believe how difficult it was to get out definitely ripped it up quite a bit but did get it off. Now I think the final question I have with this project is that the old Spud will thread all the way on nice and easy to hand tight and the new one spins on about 3/4 as you can see in the photos is this normal? I can imagine that the new threads will essentially bend to their final positioning when I finally tighten it down but I would think it would go a little further than this to be honest. I cleaned out the threads so they're very clean as well. Thanks everyone for the advice so far

@EBEBRATT-Ed @Jamie Hall @Waher @ChrisJ @Intplm.

dko

Don't forget to put the nut first!

ChrisJ

I assume you have the spud tool to install the new one?

I don't think it's possible without it?

pecmsg

You may want to order a tap and clean up the threads a bit.

ethicalpaul

Tape up the threads and put them in until you feel confident. There’s no reason to match the guy who installed the previous one 80 years ago.

we’re talking 2 psi here

Waher

Once you wrap the spud with tape or a thin layer of dope it will thread more easily than testing it by hand. Brass is softer than iron so as long as the threads in the radiator are clean (iron debris could act as an abrasive pushed by the brass if not wiped out with a rag/brush), they shouldn't get damaged by the brass spud being screwed in.

EBEBRATT-Ed

If the new spud is in hand tight in the picture you should be fine with 3 threads or so left. If the threads look good and you wire brush them out teflon tape and pipe dope and you should be fine.

As mentioned above don't forget to put the nut on.

EBEBRATT-Ed

If you don't have the spud tool, I have used a square piece of steel to insert in the spud and turn with a wrench. Sometimes you have to grind it a bit to make it fit.

midiman143

Hello everyone here is the final product. I want to thank you all so much again for helping me with this whole process. Definitely not the cleanest job ever but I think it'll be pretty effective let me know if you see anything that's alarming with what I did.

EBEBRATT-Ed

Looks good to me.

Larry Weingarten

Hi, It's purely aesthetic, but if you used a close nipple under the valve, might you be able to use fewer shims under the radiator? Really, the main thing is that is works and gives you some heat!

Yours, Larry

EBEBRATT-Ed

Or a street elbow. But I dislike street elbows almost as much as bushings.

midiman143

Larry Weingarten said:

Hi, It's purely aesthetic, but if you used a close nipple under the valve, might you be able to use fewer shims under the radiator? Really, the main thing is that is works and gives you some heat!

Yours, Larry

Ya I did buy a close nipple but since this was my first time using any kind of black iron pipe nipples I wanted that little bit of pipe to grab onto in cased I really botched something up and had to take it off again

Dan_NJ

Looks good, and it seems like maybe it could be lower using a 45 degree elbow and maybe a street 45 (or another 45 elbow), into a straight radiator valve? I guess it would wind up farther from the wall and a little further to the right?

KarlW

I realize this issue is resolved, but I thought I’d share a story from yesterday.

I replaced I replaced a Hoffman 17C steam trap with a much newer Hoffman 17C.

I thought I wouldn’t have to touch the spud because it is the same model but I was wrong - turns out the nuts had different threading!

For what its worth the old one was stamped Hoffman 17c (Lowercase) and the new one is stamped Hoffman 17C (uppercase).

EBEBRATT-Ed

I think it's fine. If you don't like the shims, you could always cut some wood blocks and stain or paint them slide the shims out and slide the blocks in.