Forced Hot Water Air Test Leak

rickster05

I'm in the process of hooking up old Crane baseboards for a new zone. I was unable to locate new push nipples to connect 2 of the units. I did a bench test using pipe dope and pressurized the radiators to 15psi. They held pressure for 24 hrs. After installing, I am now loosing just under 1psi in 24 hrs. My question is, once hooked up and running, will the scale in the boiler water once circulated stop the leak between the 2 units at the slip nipples? I really want to repurpose these baseboards as I think there great!

newagedawn

is that where it is leaking from?, if so fix it, meaning take it apart and re install with tape and joint compund

rickster05

Can't use tape on the slip nipples. Already took it apart once and applied more pipe dope to nipple. First time the leak was audible and would not hold any pressure. Second time, no audible leak and only losing about 1 psi in 24 hours.

HVACNUT

Things are always better on a bench test aren't they?
Is it possible the wall is not exactly plumb and the connection is making a V at the joint?
Try loosening some screws and shim in places for a flush connection.
Then spackle compound to "even out" the wall.

rickster05

I know, right. There is a slight v at the joint. Might give your suggestion a try. The system has been holding 13 psi now since 9 pm yesterday. I'm thinking my that if this does not change I may just leave it and try filling and running the zone on a heat load to see what happens. I have a Watts 911 and believe it is set to 15psi, but I could adjust it to 13. I'm still of the belief that it will stop once boiler water is circulating for a while.

Jamie Hall

Are you testing with air in the system, or water? I presume the system is closed, and the expansion tank is valved off. In either case -- assuming that you have a closed system -- remember that air or water expands or contracts with changes in temperature, only in a closed system it can't do that much -- and so it will change the pressure. Air less so than water.

ChrisJ

It's been my experience that things will plug up unless you want them to. If you want a leak to plug up it never will and if you want something to not leak, it will never plug up.

I'd say if you put it into use it's likely going to get worse over time.

That's just a guess.

EBEBRATT-Ed

If you take it apart and redope it try Hercules Grip.

Also, do you have any air vents that are not isolated?. Expansion tank isolated as @Jamie Hall mentioned

bob_46

Take apart clean, JB Weld .

rickster05

Thank you for the replies. It is a closed system under test. I am now planning on isolating the radiators from the zone using shut offs and boiler drains. My thought is to run the zone, get it hot by using the boiler, then close/isolate the radiators add J.C. Whitlam Seal-Tyte Boiler Sealer and use a fluid pump hooked up to the two boiler drains to circulate until the leak stops. Perhaps a bit overdesigned...

I do like the JB Weld suggestion, I just don't see how once cured, I could position the radiator 1-7ft and 1-6ft now 13ft into place with out causing it to come undone. I also thought of using ExpandEx but I think it would render a similiar result, plus I have already painted the units... These units only have 1 bolt in the middle of the push nipples for connecting unlike Burnham BaseRay. Poor design I'd say.

My grandfather was a licensed plumber since the 1950's. I learned an aweful lot from Hank regarding plumbing copper and black pipe the good old fashioned way. I know he's looking down saying, just run it and it will seal itself Ricky. Oh well. Any additional remarks are greatly appreciated.

rickster05

Forgot to mention. I will most certainly drain the sealer and flush the line once the leak has stopped. No interest in running the sealer through all my boiler components.

Jamie Hall

A push nipple is a little like a union in one critical way: it depends on the mating surfaces of the nipple and the sections being absolutely smooth and properly aligned. If that is true, then it takes remarkably little force to get it to seal. If it isn't true...

Of particular note, if there is a leakage path -- a scratch or corrosion roughness -- on one of the mating surfaces, it may be almost impossible to get a seal. Worse, the leakage path will always get worse with time.

First thing I'd do at this point is to take the thing apart and check those mating surfaces. If there are scratches or deep corrosion pitting, you might be able to get away with a small amount of JBWeld -- while it is disassembled -- and letting it cure, then machining it down. If they are minor, you might also be able to get it by smoothing it very carefully with fine emery paper -- being sure to maintain the taper and roundness! Then reassemble it, and use a long steel straightedge to be certain that the sections are really truly aligned before you tighten things up. Shim the feet or whatever is holding it up at that point as required.

Then try it again...

jumper

I've had luck with epoxy specifically advertised for copper plumbing. I heat the problem to finger pain and then squirt away. But if you ever want to disassemble I don't know how to remove the stuff.

NY_Rob

OP- are you sure you can't get new push nipples for the baseboard?

I just installed 20' of Burham BaseRay (4-sections of varying length) and the supply house mistakenly gave me 1" push nipples when I picked up the order. I had to exchange them for 3/4" nipples the next day. Apparently they do stock different size push nipples....

Burnham suggests center floor supports every few ft to prevent sagging/leaks between sections. Does the Crane BB have center supports? I applied Mega-Loc to the nipples before joining the sections.

FWIW- Burnham BaseRay (and GOV-Board) only use a single tie-bolt as well to join sections.

rickster05

Wanted to follow up. Thank you for all the feedback. Put the zone into commission with no leaks. Guess my grandfather was right regarding boiler water and any ips connections! I did use radiator supports to keep the units plumb. Fabricated end and connection caps using pvc boards.

Happy with result!

NY_Rob

Nice job on the trimwork... looks great!

rickster05

Thank you!