Boiler/piping woes

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Discussion

Mopey

Original Poster:

2,396 posts

155 months

Friday 26th February 2021
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Lincsls1 said:
If you have a few small weeps, you're likely to be having to fill it like you are. Often though, the amount of water you're putting back in 'sounds' a lot more than it really is.
If the leak was under the floors from upstairs I'd expect to see it on a ceiling at some point. If its under the ground floor, you'd never know.
Like I said, thoroughly check the radiators/valves/unions. This is generally where the leaks are.
As for the leak sealer, it is easy enough to add. Best through a radiator, ideally a ladder towel rail. Isolate and drain radiator, remove top blank piece, open opposite side bleed, pour leak sealer into radiator. Refit blank, close bleed, open valves, bleed rad till air gone, top boiler up, run heating to circulate. Allow a couple of days for effect and expect to top up once or twice again. Cross fingers!
It does work though I assure you, assuming it isn't a severe breach or another problem.
I am suggesting this solely based on the boiler being eliminated though.
The other most common pressure problem is the boiler expansion vessel being flat or too small for size of house causing PRV to blow outside.
Thankyou though got to be honest here this is beyond me and my ability when it comes to radiators and plumbing- I’m not the best at DIY was pleased with the help of this thread to have isolated the boiler and identified it’s in the system.
As I say I will check and double check all of the valves and areas that we could have a leak. It’s been 9 days of refilling the boiler daily if not twice a day- surely it’s a matter of time till we see evidence but I would rather intercept it before a disaster!

Mopey

Original Poster:

2,396 posts

155 months

Friday 26th February 2021
quotequote all
ro250 said:
Have you kept the bag over the outside drain pipe and kept this under monitoring? I does sound like you've eliminated the boiler but when the valves are closed wouldn't there still be some water in the boiler area which may be leaving through the condensate overnight?

We had a similar situation recently and it turned out to be the heat exchanger. It wasn't the first thing our plumber checked as the boiler is only a couple of years old. I too, was thinking where's the water going as was topping up daily. Luckily fixed under warranty.
This was the result I was hoping for but evidence seems to suggest this is not the case. I still have the bag on the end of the pipe just in case.

No ideas for a name

2,188 posts

86 months

Friday 26th February 2021
quotequote all
Just a thought, but if the system is on and calling for heat, maybe all of the leaking water is being evapourated rather than pooling and showing its location.

Maybe try a night where the system is off, but pressurised to 2bar. If, in the morning the presure has dropped, you may be able to locate a wet joint/area?

Lincsls1

3,336 posts

140 months

Friday 26th February 2021
quotequote all
Hi Mopey, important question.
On Wednesday when your filled the boiler up to 2bar and then isolated the boiler, was the entire system AND boiler stone cold?
If you had been using the heating before you did this then you won't have got an accurate result when you open the isolation valves the following morning. This is because the pressure drop you noted could simply have been the contraction of the water as it cooled in the radiators!
If you did it all stone cold, then ignore me, otherwise you need to repeat Wednesdays test ensuring you turn the boiler totally off say 1hr before setting it to 2bar and then isolate. The next day immediately open the valves and note any drop again.

I'm saying all this because as others have said it could still be an internal leak within the main heat exchanger.
Putting a bag over the condensate pipe with the boiler off and cold will prove if it isn't leaking internally WHEN cold.
Trouble is, the leak may occur only when the boiler is running, heat expands metal and it might be this is when it weeps through to the condensate circuit. You'd struggle to tell because when the boiler is running it creates condensate water anyway and any leak will just add to it and drain away.
Hope I'm not confusing matters.


Mopey

Original Poster:

2,396 posts

155 months

Friday 26th February 2021
quotequote all
Lincsls1 said:
Hi Mopey, important question.
On Wednesday when your filled the boiler up to 2bar and then isolated the boiler, was the entire system AND boiler stone cold?
If you had been using the heating before you did this then you won't have got an accurate result when you open the isolation valves the following morning. This is because the pressure drop you noted could simply have been the contraction of the water as it cooled in the radiators!
If you did it all stone cold, then ignore me, otherwise you need to repeat Wednesdays test ensuring you turn the boiler totally off say 1hr before setting it to 2bar and then isolate. The next day immediately open the valves and note any drop again.

I'm saying all this because as others have said it could still be an internal leak within the main heat exchanger.
Putting a bag over the condensate pipe with the boiler off and cold will prove if it isn't leaking internally WHEN cold.
Trouble is, the leak may occur only when the boiler is running, heat expands metal and it might be this is when it weeps through to the condensate circuit. You'd struggle to tell because when the boiler is running it creates condensate water anyway and any leak will just add to it and drain away.
Hope I'm not confusing matters.
Hi Lincs. I realised this so tried again last night but from about 5pm so heating was stone cold till this morning when I went to check the boiler and put the valves on. It had hardly moved so I’m fairly sure sadly it’s a leak on the system somewhere! Boiler would have been my preference.

Mopey

Original Poster:

2,396 posts

155 months

Friday 26th February 2021
quotequote all
Hey guys quick question. Heating is on after a refill- quick question how much should be coming out of the condensate pipe.
See attached picture it’s up to my finger on the picture. Have just left the bag on from opening the valves this morning.
It’s a fair amount of water??




After googling looks like it’s normal... ah man.

Edited by Mopey on Friday 26th February 17:06

ro250

2,750 posts

57 months

Friday 26th February 2021
quotequote all
Mopey said:
Hey guys quick question. Heating is on after a refill- quick question how much should be coming out of the condensate pipe.
See attached picture it’s up to my finger on the picture. Have just left the bag on from opening the valves this morning.
It’s a fair amount of water??




After googling looks like it’s normal... ah man.

Edited by Mopey on Friday 26th February 17:06
I think that probably is normal as they chuck out quite a bit in condensing mode. The key measure is whether it carries on when the system is off. I'd top my system up when I had a faulty heat exchanger and if I didn't use the heating straight away the pressure would have already dropped by the time I came to use it as the water was just dripping straight out.

Mopey

Original Poster:

2,396 posts

155 months

Monday 1st March 2021
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Update. Have now contacted leak detection people as the next stage as having to refill the boiler twice a day and still no sign of a leak anywhere!

Lincsls1

3,336 posts

140 months

Monday 1st March 2021
quotequote all
Mopey said:
Update. Have now contacted leak detection people as the next stage as having to refill the boiler twice a day and still no sign of a leak anywhere!
Let us all know how you get on if you would, always nice to read the solution/conclusion of a problem. smile

Mopey

Original Poster:

2,396 posts

155 months

Friday 5th March 2021
quotequote all
Leak detection company found our culprit they pumped gas through the system and we got a hit—-in the loft.
There is now a little damage on the ceiling below but hardly anything, could have been far worse. think it was escaping in part down a shaft by the chimney seems there’s a bit of a hole there.
So getting some of the bits replaced as it’s a bit of a bodge apparently.
So taken a hit on the excess and paying for the repair but at least we have found our leak.


Thankyou to everyone for all your advice and help- a redeeming quality of Pistonheads. Some great community support.


ro250

2,750 posts

57 months

Friday 5th March 2021
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Great outcome - not a horror reveal of damage and found quite quickly too. I bet that's a relief!

Mr Pointy

11,223 posts

159 months

Friday 5th March 2021
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Good to see it's been found & didn't mean ripping too much up.

Did they use some type of gas they could use a detector to find? Do you know what gas it was?

Mopey

Original Poster:

2,396 posts

155 months

Friday 5th March 2021
quotequote all
Not sure what the gas was but they then used a detector.
When the floorboard was up you could hear the escape of water/gas.

Lincsls1

3,336 posts

140 months

Friday 5th March 2021
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thumbup

Mopey

Original Poster:

2,396 posts

155 months

Friday 5th March 2021
quotequote all
Turns out the joist had been absorbing all of the water- which is why there’s very little on the ceiling it was moving along the joist.
So putting the rad on nearby and leaving the carpet and floorboard up to help it dry out for a few days.