UFH pipe leak in uncommissioned system??

[i5hyp]

I have an uncommissioned wet underfloor heating system in screed. Yesterday the joiner was screwing into the newly tiled floors and may have potentially screwed into a UFH pipe (on the borderline of pipes). The pressure gauge on the UFH manifold was showing around 1.5 bar and dropped to around 1.3 over 24 hours...

I'm getting paranoid that this pressure gauge reading drop is due to the potential damage. Is there any simple way to check whether he has or not? Is it normal to have pressure drop like this. BTW Iv never checked the pressure gauge on the manifold until yday so don't know if it's normal to drop like this.

 

[Madrab]

Invariably, if the pipe has been knicked, then it would usually show as a wet patch.

No there shouldn't normally be a drop in pressure unless it's newly been pressurised and it's still working air out of the system through say an AAV on the manifold and it still needs to stabilise.

 

[Mr Chibs]

The weather also can change the gauge, I thought I’d got a leak after plumber had made final connections and pressurised the system... day or two later it was going down according to the gauge.

Once it reached a certain level it stopped.
If your gauge has a red marker, you might be able to twist with screwdriver to line up with the black marker... you can then monitor how much it’s losing.

 

[Laurieo]

Can you not take out the screw ? to see if pressure drops more .

 

[i5hyp]

We took out the screws to check all the screws and no water or any signs, although I guess it would leak below l presume? My buildup is tile, adhesive, decoupling membrane, pipes in screed.

The gauge has dropped from 1.6 to 1.3ish bar and is stable at that. There is no other heating on in the property so it could be change in temperatures etc.

 

[Madrab]

although I guess it would leak below l presume

Yes and no, it would leak down as far as the bottom of the hole but it would also fill up and then spread out, darkening the crete. It's pretty obvious when it gets wet TBH, unless the crete hasn't dried yet.

 

[i5hyp]

So the screws were all taken out and we waited a while and there was nothing coming up through the screw holes or the floor has remained dry so I think it seems to be OK.The only thing puzzling me is the pressure gauge dropping. This system has been in for quite some time so I'm hoping it's just normal pressure drop. Like I said I would never look at it before so don't know if it would be normal to drp

 

[i5hyp]

Thanking you for all your help

 

[Madrab]

Just keep monitoring it over the next few days, there will always be slight pressure swings as the mass naturally air warms and cools or as any trapped air vents out. As long as it doesn't drop right down then I wouldn't worry too much about it.

 

[i5hyp]

So Iv been checking over the last 3 days. We have dropped from around 1.6 to around 1.2 now. Speaking to the installers, they said the drop in the gauge is normal and will fluctuate until you commission the boiler.

If there was any damage, damp patches are the most common signs but as Iv tiled the floor already it would be more difficult to see. Fingers crossed there are no issues and Il keep praying I don't have to rip the flooring out to fix.

 

[dilalio]

Did joiner not know there was UFH in the floor? Glue would have been better!

 

[i5hyp]

It was probably my mistake. I assumed he wouldn't be screwing into a newly tiled floor, maybe he would just build a frame and screw against walls and I had forgotten to mention the pipes as assumed he was around when it was being laid. An oversight that I'm hoping doesn't cost me..

 

[dilalio]

It was probably my mistake. I assumed he wouldn't be screwing into a newly tiled floor, maybe he would just build a frame and screw against walls and I had forgotten to mention the pipes as assumed he was around when it was being laid. An oversight that I'm hoping doesn't cost me..

Don't stress.
Happens all the time.

 

[MeldrewsMate]

If it's presently 'uncommissioned' you could ask the commissioning fitter to disconnect the suspect UFH pipework and pressurise it using a hydraulic pump, usually up to about 10 bar. This will quickly reveal any weeping pipe.

 

[lostinthelight]

Not that I know much about UFH , I pressurised mine to test with hosepipes connected to the manifold, our pressure is over 5 bar.