Feck - frozen ufh causing leaks?

[Moonshine]

4 minutes ago, Bonner said:

 

What exactly makes you think it has frozen?  You’ve got water coming out of the manifolds which will be colder than in screed. Also you had 1 bar of pressure. If it has frozen, you might expect the pressure either off the scale due to expansion, or zero if it’s leaking (although it depends if and where an ice plug may have formed). I would be surprised if it has frozen and even more surprised if UFH pipe has burst.

 

The water in the external hosepipe feeding the site are frozen you can hear the ice crack in the hose pipes when they are bent.

Regarding the pressure I think that the one bar it's measuring is at the manifold and an 'ice plug' has formed.

I do hope that I am wrong, going in there in a bit and see of the patches have changed from those marked out last night

[Andehh]

Good luck, I spent an 90mins middle of the night checking our floor, our pressure was at 4.5 bar. Floor temps looking worryingly low (-1...) though. 

 

Heading back in 30mins to meet builders team when they arrive, and will be ringing him on the way. 

 

Feck me.

Edited December 13, 2022 by Andehh

[LA3222]

Isolate and pressure test the individual loop which you think it may be. I have a similar issue with my first floor UFH - wet patch kept appearing, at first I dint really pay attention to it. After a while I started messing with the UFH in earnest and realised the pressure kept dropping - isolated and tested the loop to confirm it was leaking. I must have put a screw through it by accident - much easier for me to fix though as it's in a pug mix under 22mm flooring. It has been like that for over a year now - I've got the repair coupler, just haven't done it yet. The affected loop is just closed off.

[Roundtuit]

Just a thought... if a pipe bursts due to freezing, it doesn't usually leak until it thaws, and if the pipe is encased in screed, the I'd have thought any bursts would be around the manifold perhaps.

[Moonshine]

1 hour ago, Roundtuit said:

Just a thought... if a pipe bursts due to freezing, it doesn't usually leak until it thaws, and if the pipe is encased in screed, the I'd have thought any bursts would be around the manifold perhaps.

 

It would freeze and thor during the day. Spoken to the ufh heating material supplier (5 mins from site). They strongly don't think that its there kit. As it's been pressure tested and it was o.k then not the pipe.

 

They told me it's best practice to take the water out after pressure testing and not to have water in the pipe over cold unheated periods. In thier opinion its an oversight of the installer.

 

I have sent the pictures to the plumber..... 

[Andehh]

Long chat with my builder, and his plumber. Both long standing and both gave proven fastidious. 

 

Neither are the slightest bit worried, nor have ever come across pipes freezing and splitting. 

 

Both have seen joints fail, manifolds spring leaks, fitting come off through frost but both were totally comfortable with the pipes. 

 

Not sure how I feel about it, but I can't force them to do much, though they are going to drain as much of it as they can for my peace of mind. 

 

When I told them about that grand designs episode where the Ufh froze and split they were very surprised, and asked me to find the episode. Could only suggest damage during installation (rare) or very cheap/old pipe work. 

[Dave_madl]

11 minutes ago, Andehh said:

Long chat with my builder, and his plumber. Both long standing and both gave proven fastidious. 

 

Neither are the slightest bit worried, nor have ever come across pipes freezing and splitting. 

 

Both have seen joints fail, manifolds spring leaks, fitting come off through frost but both were totally comfortable with the pipes. 

 

Not sure how I feel about it, but I can't force them to do much, though they are going to drain as much of it as they can for my peace of mind. 

 

When I told them about that grand designs episode where the Ufh froze and split they were very surprised, and asked me to find the episode. Could only suggest damage during installation (rare) or very cheap/old pipe work. 

When my uncle built his houses, he also filled his pipes with water to pressure test then didn't drain them over winter, although the house was wind and water tight the pipes still managed to freeze and split in several places during a few cold winter nights (probably not what you want to hear) but it does happen, this resulted in us having to cut up round all the walls to remove the whole ground floor and then redo it. 

[Andehh]

Thanks Dave, yeah - really not sure how to proceed. They have agreed to drain the system as best they can, and ill ask them to seal the place up more so! Not sure there is much else we can do other then fingers crossed.   

[Kelvin]

What a pia. It’s something that seems wholly avoidable though which is even more of a pia as you’d expect a competent plumber to account for it. 

[PeterW]

Pressure testing the individual loops is probably the best approach but it’s a ballsache to do. Unless the manifold is frozen solid I can’t see how pipe in concrete will split over a joint blowing out unless it was damaged during installation. 

[Moonshine]

16 minutes ago, Andehh said:

Thanks Dave, yeah - really not sure how to proceed. They have agreed to drain the system as best they can, and ill ask them to seal the place up more so! Not sure there is much else we can do other then fingers crossed.   

 

This is best practice to drain system, and probably best to use an air compressor to get most of the water out, at least if there is air in the pipes the water can compress into that as it expands rather than the pipe walls

 

i would be interest to know what the grand design episode is.

 

A quick google has this is a valid issue and one that should be considered.

 

https://www.continal.co.uk/blog/preventing-and-fixing-damage-to-ufh-systems

 

Quote

3) Prevent freezing

If the site is exposed, or freezing temperatures are forecast, make sure the pipework is purged of water. Freeze damage is hard to visually detect and weakens the pipe structure, with leaks often forming several years later.

 

https://www.grantuk.com/media/3215/grant-uflex-ufh-installation-guide-rev0619.pdf

 

Quote

If the UFH is being installed in the winter, anti-freeze can be added to the system water for protection against freezing. If used, then the pipes will need to be fully flushed with cold water prior to running the system.

 

Plumber phoned, and basically says that is is a unpredictable and unforeseen issue.

[Adsibob]

16 minutes ago, Moonshine said:

 

Plumber phoned, and basically says that is is a unpredictable and unforeseen issue.

I think he's being unreasonable. By way of comparison, i haven't heard from my contractor in a couple of months. Over the weekend, out of the blue, he calls me up and says: "are you in, I need to come over and show you how to drain your external taps". So he did. The cynic in me thought "lucky I happened to be in, he really left it to the last minute", but on balance it shows he thinks ahead (just not a lot ahead)!

[Radian]

23 minutes ago, Moonshine said:

Plumber phoned, and basically says that is is a unpredictable and unforeseen issue.

How long is it since he moved here from the tropics?

[Kelvin]

The plumber couldn’t predict winter was coming and it gets cold possibly below freezing? He’s taking the piss. 

[LA3222]

1 hour ago, PeterW said:

Pressure testing the individual loops is probably the best approach but it’s a ballsache to do. Unless the manifold is frozen solid I can’t see how pipe in concrete will split over a joint blowing out unless it was damaged during installation. 

Its not that much of a pita. Close the flow and return on the manifold for each loop then open them up one at a time to see if they hold pressure. Half hour or so.

 

It should be even easier because the leak area is known so the assumed faulty loop should be easy to identify.

 

When I had to play this game I didn't know which loop was damaged so had to repeat for all 11. It was loop number 7!!

Edited December 13, 2022 by LA3222

[Bonner]

4 hours ago, Moonshine said:

I do hope that I am wrong, going in there in a bit and see of the patches have changed from those marked out last night

what do your damp patches look like then? 

[Moonshine]

5 minutes ago, LA3222 said:

It should be even easier because the leak area is known so the assumed faulty loop should be easy to identify.

 

yes the leaks that i can see are all in one loop, looking at other loop areas i can't see any other wet spots on the other loops, and am surprised that its not happened in other areas.

 

weather is warming up from the end of the week and should thaw out the UFH pipes (if they are frozen), my plan is to see how it dries out and give the problematic loop a wet pressure test up to 4 bar and see how it fairs.

[Moonshine]

14 minutes ago, Bonner said:

what do your damp patches look like then? 

 

i don't know if you are taking the pi$$ or not, but the extent of them haven't really changed but they have got damp again after my hair dryer drying (not deep drying). its about 3 degrees here, so i am not expecting much change in them.

 

I think that the only real test will be when it thaws out, and i can put the system under a higher pressure again (over the 1 bar its indicating at the moment). Also checking on the the pressure in the system if that drops as it thaws.

 

I may in the near future do a dig out of one of the biggest damp spots to expose the pipe and get an eyeball on it.

Edited December 13, 2022 by Moonshine

[Bonner]

6 minutes ago, Moonshine said:

don't know if you are taking the pi$$ or not

?! you said you going back to have a look, I am interested to know if UFH pipes do split if they freeze

[Moonshine]

15 minutes ago, Bonner said:

?! you said you going back to have a look, I am interested to know if UFH pipes do split if they freeze

 

I looked at the patches this morning, and they haven't got any bigger (yet). But yes it appears they can split if they freeze and there is guidance on this matter out there.

[Radian]

42 minutes ago, Moonshine said:

i can't see any other wet spots on the other loops, and am surprised that its not happened in other areas.

 

It could of course be that they're still frozen solid. What's the opening at the top of your photo? The wet patches seem to be only in this area. Just wondering if it's potentially colder or warmer here. I'm sorry if replies sound a bit too matter-of-fact, I think there's a lot of sympathy here and it's not even certain that you do have a problem yet.

[Kelvin]

There’s definitely a lot of sympathy. I imagine most self-builders on here will have some story to tell of problems with their build and lessons learnt either from their own experience or the experience of others. 
 

If they have frozen it’s likely they will still be frozen unless the temperature has changed significantly or is changing significantly from daytime to nighttime. Therefore why would it still be leaking water?  

Edited December 13, 2022 by Kelvin

[Moonshine]

10 minutes ago, Radian said:

 

It could of course be that they're still frozen solid. What's the opening at the top of your photo? The wet patches seem to be only in this area. Just wondering if it's potentially colder or warmer here. I'm sorry if replies sound a bit too matter-of-fact, I think there's a lot of sympathy here and it's not even certain that you do have a problem yet.

 

It's a stepped house and this is another area of the house which has a deeper floor void under the block and beam and more air under it. 

Don't worry about the tone, would love if this was just fuss about nothing and time will tell

[Moonshine]

This is what the area looked like mid August just before screed went down

 

[LA3222]

I wouldn't stress bud. Move on until you can pump it up to 3 bar with water and then see what happens. 

 

You've got a long way to go, you will have hiccups along the way and that's all this is, a PITA - yes, insurmountable - nah.

 

If it makes you feel better I asked the missus if she wanted the hob (I.e. power) installed in the island - she said no, me being a idiot chinned off a duct.

 

Guess who changed their mind🤨 Cue me chiselling though a concrete slab a long line so I could run power. That was after I had to buy a flir, Jerry rig the ufh to a willis heater in order to work out where the damn pipes were!

 

A PITA yep....but easier than I thought whilst I spent half hour stood staring at the floor and hating life😎

 

Make sure you mark the area well so when you come back to it, you can identify where the water was showing. Marker pen will not do as it will disappear as you work on the house due to dust etc.

Edited December 13, 2022 by LA3222