Psi rating for radient floor heat panel test???

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Johnny Mac

Johnny Mac

www.blueprintengines.com
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Well gents, you guys have helped me with everything from thermostat install to asphalt driveways, so here is today's conundrum.

As many of you know, I built a pole building with radiant in floor pex heating. I pressure checked the " in floor" portion and it held 50 psi for months and months.

Fast forward to today...I built and soldered the boiler/wall panel. Figured I would bench test it also. On saw horses in my basement I'm embarrassed to say, I have struggled with pressure testing. Surprisingly to me, my solders are perfect. My NPT fittings have however nearly ALL leaked with soapy water. Some ptfe thread paste, some Teflon tape, doesn't seem to matter. Tightened to fear of cracking.... can't seem to hold more than 35 psi in 24 hrs. I have repaired/redone all leaks used soapy water. Still leaks down from 40 to 30 over night. Seems to really hold there continuously.

I'm contemplating throwing in some leak sealer on startup, and letting it rip (they do sell a purpose built (base hit 2) sealer for new installs.

Operating pressure on an in floor system is 15 psi.

Thoughts??

Thanks for listening to me ramble and any assistance!!!

20230102_193747.jpg


20221229_094753.jpg
 
Can you inject some leak detecting like in an A/C system and check it with a black light?
 
You don't need to Rob, you can SEE it with soap

I would up the test pressure if you cannot get any soap

HOW ABOUT THE CIRCULATING PUMP shaft seal? Some of those are a mechanical seal. If you are unaware, that is more akin to piston rings, they may not use neoprene seals. I'm not a "boiler man." They may need water present to seal / lubricate

It may also be possible you have a defective bladder tank. I'd pull it and plug it off if any doubt. Look for anything else in that vein........AKA something that is not a connection. AND THAT includes valve shafts!!!!

Here's the other thing....anything above ground, "you can fix." If you get it down to close to "tight", I'd just fill it and run it and go from there. Leaks will become evident. Also "I guess" you are using glycol in the system, AKA antifreeze?
 
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You can tighten pipe fittings pretty tight before they break. How much are they leaking?

Sealer sounds like a good idea.
 
You caint see it with soap or dye if the leak is under the concrete.
 
Again...."I ain't a boiler man" have you researched/ checked with someone in the know that the board is laid out properly for servicing and draining, etc?
 
67Dart273 said:
I thought he said the loop was tight
Click to expand...
Well.....he also said he tested everything else and didn't find it......or did I read it wrong. I probably phukked it up again.
 
hook it up it won't leak air will leak out where liquid won't . i have a fair amount of experience with in floor heat . on your pipe thred fittings use a thin layre of dope a wrap of tape and another layre of dope and send it . no need to over think it .
 
^^^Dope it and tape it and go.
Threads ain't what they used to be. Check the country of origin of the fittings as a hint. Inspect threads closely before assembling, and chase them if there's any doubt- make sure they're clean when you start! You wouldn't believe (well, maybe you would!) some of the crappy factory thread jobs I've seen. When chasing, make sure you're not cutting any new threads, just clean them up. You don't want to mess with the taper depths of the pipe threads too much.
 
Loctite brand ptfe thread lubricant/sealant paste. It’s the only one I’ll use and I have excellent results with it.

LOCTITE 5113
 
Lamp Wick and a good pipe dope. If the threads on the pipe are cut incorrectly you can have leaks. Threaded joints done properly do not leak
When I pressure check piping usually I isolate just the piping section
Years ago I did a chill water line job. When the piping got down to 3 inch the contractor decided he didn't want to use weld fittings and he hired a guy to cut and thread pipe
He called me sometime later in a panic. They had leaks everywhere. I went out there and found every threaded joint this guy did was bad, fittings were bottoming out.
He wanted to know if I could run a bead around each leaking joint and I told him no. The fittings were malleable and I wasn't doing that. I had him order all new weld fittings and some more pipe and redid the entire job
 
Johnny Mac said:
My NPT fittings have however nearly ALL leaked with soapy water. Some ptfe thread paste, some Teflon tape, doesn't seem to matter. Tightened to fear of cracking.... can't seem to hold more than 35 psi in 24 hrs. I have repaired/redone all leaks used soapy water. Still leaks down from 40 to 30 over night. Seems to really hold there continuously.
Click to expand...

If the pipe threads were overtightened from the start, the fpt side could be distorted to the point where it will never seal. All good advise above from Del & everyone. The pump has a pressure rating too, so the shaft seal should be accounted for. If the fittings are overseas, lots could be wrong - the angle of each thread, the taper, etc.

Sure you don't have British Standard Parallel threads?

BS 21 - Pressure Tight Pipe Thread Joints

BSPT - British Standard Pipe Taper threads & BSP or BSPF - British Standard Pipe Parallel (Straight) threads.
www.engineeringtoolbox.com www.engineeringtoolbox.com
 
Professor Fate said:
Threads ain't what they used to be. Check the country of origin of the fittings as a hint.
Click to expand...
This is virtually guaranteed to be the problem.... But it sounds like you've done the proper do diligence with sealer & tape.... As others have said, air will leak where water won't... Plus the system runs at a lower pressure than you were testing at.... It didn't leak air at the operating pressure it sure won't leak water at that pressure.... Run It!!!!
 
Also you may not necessarily need to operate it at that much pressure, either.
 
Johnny Mac said:
Well gents, you guys have helped me with everything from thermostat install to asphalt driveways, so here is today's conundrum.

As many of you know, I built a pole building with radiant in floor pex heating. I pressure checked the " in floor" portion and it held 50 psi for months and months.

Fast forward to today...I built and soldered the boiler/wall panel. Figured I would bench test it also. On saw horses in my basement I'm embarrassed to say, I have struggled with pressure testing. Surprisingly to me, my solders are perfect. My NPT fittings have however nearly ALL leaked with soapy water. Some ptfe thread paste, some Teflon tape, doesn't seem to matter. Tightened to fear of cracking.... can't seem to hold more than 35 psi in 24 hrs. I have repaired/redone all leaks used soapy water. Still leaks down from 40 to 30 over night. Seems to really hold there continuously.

I'm contemplating throwing in some leak sealer on startup, and letting it rip (they do sell a purpose built (base hit 2) sealer for new installs.

Operating pressure on an in floor system is 15 psi.

Thoughts??

Thanks for listening to me ramble and any assistance!!!

View attachment 1716030660

View attachment 1716030661
Click to expand...
I know this may sound like a stupid question but did you solder any pipe to sweat adapters while they were made up?
If so thats your problem.

Hercules makes some good pipe sealants, you should check that out
Any threaded fitting that you see leaking bubbles when you apply soapy water or leak detector at 30 psi is a "leak" No way should you see anything leaking (bubbles) at those joints.
 
67Dart273 said:
You don't need to Rob, you can SEE it with soap

I would up the test pressure if you cannot get any soap

HOW ABOUT THE CIRCULATING PUMP shaft seal? Some of those are a mechanical seal. If you are unaware, that is more akin to piston rings, they may not use neoprene seals. I'm not a "boiler man." They may need water present to seal / lubricate

It may also be possible you have a defective bladder tank. I'd pull it and plug it off if any doubt. Look for anything else in that vein........AKA something that is not a connection. AND THAT includes valve shafts!!!!

Here's the other thing....anything above ground, "you can fix." If you get it down to close to "tight", I'd just fill it and run it and go from there. Leaks will become evident. Also "I guess" you are using glycol in the system, AKA antifreeze?
Click to expand...
Correct on the glycol mixture. Those are interesting points. I too wondered if it's a ball valve leaking, which is fairly irrelevant once mounted, but a bad bladder in the tank, or a pump shaft may also be the culprit.

Soapy water has stopped revealing any leaks, but to Robs @RustyRatRod point, I could turn it upside down and fill it with soapy water, and add some pressure. That may help reveal something.

Thanks!
 
Mike69cuda said:
You can tighten pipe fittings pretty tight before they break. How much are they leaking?

Sealer sounds like a good idea.
Click to expand...
Tiny little soap bubbles. I have always been told plumbing projects need to hold x2 pressure fir 24 hrs. I'm not a code contractor, but have always used that ballpark.

They are TIGHT.
 
67Dart273 said:
Again...."I ain't a boiler man" have you researched/ checked with someone in the know that the board is laid out properly for servicing and draining, etc?
Click to expand...

67Dart273 said:
I thought he said the loop was tight
Click to expand...

RustyRatRod said:
Well.....he also said he tested everything else and didn't find it......or did I read it wrong. I probably phukked it up again.
Click to expand...

Yeah, floor loops are good.

Yes its laid out correctly. It's a carbon copy of a pre assembled panel sold at menards.
 
Johnny Mac said:
Yeah, floor loops are good.

Yes its laid out correctly. It's a carbon copy of a pre assembled panel sold at menards.
Click to expand...
Then you ain't in too bad a shape. At least you ain't gotta bust up any concrete. lol
 
Demonic said:
If the pipe threads were overtightened from the start, the fpt side could be distorted to the point where it will never seal. All good advise above from Del & everyone. The pump has a pressure rating too, so the shaft seal should be accounted for. If the fittings are overseas, lots could be wrong - the angle of each thread, the taper, etc.

Sure you don't have British Standard Parallel threads?

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Click to expand...
Yes, it's all NPT. Everything was new from menards. Probably overseas origin. I don't think I over tightened them originally, but did sure give them hell after re taping/thread sealing.
 
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