UFH pressure dropping, screed tomorrow!

[Mat1980]

My plumber filled the loops with cold water to 2.1bar on Friday. Today on Sunday we're at 1.5bar. There are no obvious leaks in the actual pipes and nothing is wet on the manifold.

Should I be worried?

The pour has to happen tomorrow

 

[just pumps]

What does your plumber say?

 

[Mat1980]

What does your plumber say?

No response from him yet.

 

[just pumps]

Well he is in for a suprise come Monday morning isn`t he.
Going back to your Q I feel you know the A don`t you.

 

[Mat1980]

Well he is in for a suprise come Monday morning isn`t he.
Going back to your Q I feel you know the A don`t you.

Googling has thrown up conflicting information hence the thread. I'm trying to figure out a way forward given the pour is happening tomorrow.

If the problem is somewhere on the manifold is that something that can be rectified after the pour?

 

[muggles]

If the problem is somewhere on the manifold is that something that can be rectified after the pour?

Yes, but if it's on the pipe then it can't be. Best to delay the screed until the issue can be found and rectified. You'll regret it later if you try to rush things now

 

[Bodgedbuild]

Your problem probably isn't a problem if you can find no leaks. You probably have 100's of metres of pipe that will "relax" slightly once subject to pressure. Really though the whole system should have had the pump running for a couple of days before to get all the air to settle and it should have been re-bled and topped up. Finally the plumber should have pressurized the system to around 6 bar and left that pressure in the system during the pour and initial cure. I think I would be tempted to open the fill loop to try and get some pressure in it at least a fair bit higher than normal running pressure.

 

[just pumps]

Really depends on what the manufactures say`s. I`m reading that 6bar test for short time only or the pipes can be stretched and deform with 2bar pressure whilst the screed is poured and sets but as I said the manufacture is king.

 

[Bodgedbuild]

Really depends on what the manufactures say`s. I`m reading that 6bar test for short time only or the pipes can be stretched and deform with 2bar pressure whilst the screed is poured and sets but as I said the manufacture is king.

That's what John Guest advised for my pipe while installing and pouring. I left the rest of the system isolated while holding at this pressure but I think most companies advise 4 to 6 bar to be held in the UFH pipes during pour and cure. The burst pressure of the John Guest stuff is over 60 Bar by the way! Edited...60 Bar!

 

[Bodd]

Poor show from the plumber

I would imagine AAV may have released air. I think you'll be OK.

 

[Mat1980]

Thanks guys. Still no response from the plumber :/. Funny he was way easier to contact during lockdown.


I couldn't delay the screeding but had no drop overnight so hopefully it's not an issue.

I'm going to make sure all the rest of the central heating is done before anything else happens.

 

[Bodd]

Thanks guys. Still no response from the plumber :/. Funny he was way easier to contact during lockdown.


I couldn't delay the screeding but had no drop overnight so hopefully it's not an issue.

I'm going to make sure all the rest of the central heating is done before anything else happens.

Id text him saying there's still a drop, and that it's been screeded

 

[HERTS P&D]

I would suggest you find a new plumber for any other work, one that picks up the phone when called, or at least calls you back.

Andy