Odd-sized fitting

FittingMonkey

I have an old radiator with fittings that are somewhere between 1-1/2" and 2".  Does anyone have an idea of what I might be working with and where I can find such fittings?  No place online (based on my research) has an 1-3/4" fitting, which is what it appears to measure out to be.

ChrisJ

ID vs OD

Not sure if this is what you are seeing but an 1 1/2" pipe has a larger outside diameter as 1 1/2" is the inside diameter.



1 1/4" pipe has a outside diameter of 1.660"

Please see the following URL :

http://academic.evergreen.edu/projects/biophysics/technotes/fabric/pipe.htm

FittingMonkey

Image

Not sure if I stated this correctly. I tried a 1-1/2" fitting and it was too small.  A 2" fitting was too big.  I don't know how to measure the inside of the union. 



This is what I am looking at:



http://www.doityourself.com/forum/attachments/boilers-home-heating-steam-hot-water-systems/4583d1350847359-3-4-unions-different-size-threads-img_5018.jpg

SWEI

union threads

are not the same as pipe threads.  What are you trying to accomplish?

FittingMonkey

Union threads

I want to connect this old radiator into my existing system. Before I connect it, though, I need to pressure test to make sure there are no leaks.



I went to Menard's and purchased 1-1/2" galvanized fittings to fasten on to the radiator ends.  This worked with a previous radiator which used 1-1/4" fittings.



I tried to tighten the 1-1/2" fitting to the radiator opening (union?), but it was too small.  So I went and got a 2" fitting, but it was too big.  Based on what I'm looking at, I'd need something in between a 1-1/2" fitting and a 2" fitting, but no plumbing supply place carries those.

SWEI

keep or replace the union

Either remove the union from the old radiator, or use both halves of it.

FittingMonkey

Removing the union

Any suggestions on how I could remove the union from the radiator?  I was told to use something called a "breaker bar" and a propane torch.

FittingMonkey

Spud wrench

I meant a "radiator spud wrench" not a breaker bar.

SWEI

spud wrench

are there nubs inside the spud?  If not, you might try a nipple wrench.

FittingMonkey

Unions removed!

I picked up a radiator spud removal wrench from Gopher Plumbing Supply for $14.95.  I eagerly drove home, took a whack at it, and they came off on the first try. Sweet!



First of all, can someone please tell me what the correct term is for these pieces (photo attached)?  I want to order some new ones that will work with 1-1/2" or 1-1/4" fittings.

Rod

Fitting

Hi- They're usually called radiator spuds and come as a matched set with the fitting (radiator valve, elbow) that to which they are attached. Normally the union flanges AREN'T interchangeable with the same type of fitting made by another manufacturer. They might be close but usually you'll have leaks. As was pointed out earlier in this post, the threads on the flanges (Spud nut) are straight thread rather than tapered pipe thread

- Rod

FittingMonkey

Jackpot?

So if I buy the radiator "valve" from Pex it actually contains three pieces: (1) the valve, (2) the spud, and (3) the spud nut?



http://www.pexsupply.com/Matco-Norca-BARVY-1250-1-1-4-FIP-x-Male-Union-Steam-Angle-Radiator-Valve-4649000-p

Rod

Matched Set

Yes! It comes as a matched set. Is the radiator inlet 1 1/4 inch?

- Rod

FittingMonkey

Not sure

Not sure if it's 1-1/4", I'll need to measure it. I think it's more of a 1-1/2"



Do you know of a good document on how I can measure fittings?  Isn't the ID what we go by with cast iron or galvanized?

Rod

Determining Pipe Size

The best way to determine the pipe size is by measuring the outside circumference. I've attached a chart which gives the common pipe size measurements.

- Rod

FittingMonkey

Measurements taken

The diameter appears to be 1.6" based on my measurements (photo below).  So that would make it 1-1/4" correct?

Rod

Pipe Thread Sizing

It would seem to be 1 1/4 inch pipe.  I've attached a pdf  on pipe thread that might be of interest to you.

- Rod

FittingMonkey

What about the "other" side?

Confirmed that 1-1/4" is the right size for the radiator.  So if I purchase a hot water radiator valve, it sounds like I'll be okay for one of the sides (since a spud is included), but what about the other side?  I don't want to buy a valve for both sides!



I could buy a 1-1/4"x close brass nipple, but it won't have the notches inside it to tighten using the radiator spud wrench.



Ideas?

FittingMonkey

Pressure-testing now

The fittings are 1-1/4" which I was happy about. I purchased a plug for one end and concocted a pressure-testing device for the other end.  I raised the pressure to 60 PSI and, after an hour, it was at 55 PSI, but I think it was do to a leak in one of my fittings.  I tightened everything up and increase the pressure to 70 PSI.  If by this afternoon I'm above 60 PSI, I'll be happy.  It's hard to know for sure if all my fittings are secure enough to prevent even the most minimal air leak.



Tester:

1-1/4" close >> 1-1/4" to 3/4" reducer > 3/4" close > 3/4" to 1/4" reducer > 1/4" T

T1 = 1/4" PSI gauge

T2 = 1/4" close > 1/4" to 1/8" reducer > 1/8" close > AIr compressor nozzle

Rod

STOP!

Wow!  You DON'T want to do this!  You are creating a potential bomb that could kill you!

    If you ever need to pressure test that high you want to completely fill the radiator with water first and then use small amount of compressed air. Since water doesn't compress, if the radiator bursts, the flying shrapnel is minimal. Using all air, the air expands and throws pieces in every direction. I'm assuming you're going to use the radiator for steam which would mean that the working pressure would be under 2 PSI so there is no need to test it at high pressure. A 10 PSI test would be plenty. Attached is a photo of an air tank that blew up at just over 75 PSI. Luckily no one was killed.

- Rod

Edit: After I posted this I saw your previous post and from that realize you are probably using this radiator for HW.  The dangers remain the same. If you are going to test it keep the pressure to a minimum level and you might consider using water to test it instead of compressed air.

FittingMonkey

Hot water radiator

Thank you for the suggestion.  I reduced the PSI to 20, since that is the load that is on my existing system.  I should clarify that this is for a hot water radiator system, not steam.



After two hours, PSI dropped from 70 to just about 60.  Not sure if this indicates a leak with the radiator or just a leak with my fittings.

ChrisJ

Hot water?

You do realize this is the steam section? 

FittingMonkey

Yes, hot water

I do realize this is the steam section. I couldn't find a hot water section (n00b?), so I figured this would be the next best thing.

ChrisJ

Well..

The steam section is where all of the cool people hang out so I don't blame you.