Boiler/piping woes

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Discussion

Mopey

Original Poster:

2,388 posts

154 months

Monday 22nd February 2021
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Hi everyone, feels like one of those things that may be impossible to get help on the forum with but worth a go.
House: semi detached, Edwardian- around 16 rads on three floors.
Boiler is a Baxi combi boiler and since Thursday has been throwing E119. Low pressure. I refill twice a day and error comes back again.
Have had plumbing company out twice now. First time they serviced - let it settle, the air thing needed re doing- e119 the next morning.
Had a guy out today same company who checked the overflow stuff (I had put a bucket underneath over the weekend) no water in it.
So he says must be the pipes. Has taken one of the rads off the system in our front room that we can’t see any water damage or check pipes (under the flooring) and they are not accessible without destroying the flooring!
Most other places are either visible or above other rooms where we would see a leak through the ceiling?

My questions are; how much water are we talking about leaking? is is it possible it’s the boiler not the pipes? Basically I don’t know if we can afford to be ripping up the whole place finding a pipe and then discover it’s the boiler, But the engineer almost ruled out the boiler.

Feeling a bit of a loss with it and it feels totally out of our control! Can get heat but having to keep refilling- so the water is going somewhere.

Has anyone had a similar experience? Or other things I can suggest?
Do national companies when they replace boilers fix editing pipe works too so could solve our problem?

Insurance seems to suggest we are covered for damage finding a leak but not the leak itself.
Thanks in advance.

Brinyan

382 posts

92 months

Monday 22nd February 2021
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Is it a condensing boiler? I had a system loosing pressure, with no evidence - no damp patches, no suspect rads or valves, no water from PRV. Ended up cutting condensate pipe, put bucket beneath, ensured boiler wasn’t run & overnight water came out of condensate pipe confirming that the heat exchanger was leaking.

Mopey

Original Poster:

2,388 posts

154 months

Monday 22nd February 2021
quotequote all
Brinyan said:
Is it a condensing boiler? I had a system loosing pressure, with no evidence - no damp patches, no suspect rads or valves, no water from PRV. Ended up cutting condensate pipe, put bucket beneath, ensured boiler wasn’t run & overnight water came out of condensate pipe confirming that the heat exchanger was leaking.
Yes I think so. Think this is the next step. Even after isolating the potential rad pressure has dropped again... it’s just going without heating for a couple of days is not ideal...

andySC

1,187 posts

157 months

Monday 22nd February 2021
quotequote all
If the boiler is a Baxi Duo-Tec or similar close off the outermost of the 2 isolating valves underneath the boiler. I’d then turn off the power on the boiler & leave sat overnight. If the pressure drops with the valves turned off then the leak is on the boiler, as mentioned it’ll likely be the heat exchanger that has failed. If in the morning the pressure hasn’t altered open up the isolation valves, if the pressure drops straightaway the problem is on the system pipework.

robwilk

818 posts

179 months

Monday 22nd February 2021
quotequote all
andySC said:
If the boiler is a Baxi Duo-Tec or similar close off the outermost of the 2 isolating valves underneath the boiler. I’d then turn off the power on the boiler & leave sat overnight. If the pressure drops with the valves turned off then the leak is on the boiler, as mentioned it’ll likely be the heat exchanger that has failed. If in the morning the pressure hasn’t altered open up the isolation valves, if the pressure drops straightaway the problem is on the system pipework.
this plus 1 I had the same problem and it was concluded it must be the down stairs UFH leaking in the slab as no visible leaks could be found . Some kind PHer recommended pressurising the system up and closing the valves under the boiler.
This proved the boiler to be leaking and not the system despite having baxi out twice and they said it was the UFH pipes.
Turned out to be the primary heat exchanger leaking into the combustion chamber.

Mopey

Original Poster:

2,388 posts

154 months

Monday 22nd February 2021
quotequote all
andySC said:
If the boiler is a Baxi Duo-Tec or similar close off the outermost of the 2 isolating valves underneath the boiler. I’d then turn off the power on the boiler & leave sat overnight. If the pressure drops with the valves turned off then the leak is on the boiler, as mentioned it’ll likely be the heat exchanger that has failed. If in the morning the pressure hasn’t altered open up the isolation valves, if the pressure drops straightaway the problem is on the system pipework.
Is this a DIY thing or need an engineer thing?
I have done the valves for refilling the boiler. I just wouldn’t want to make it worse.
It is indeed a baxi duo tec 28 I believe.

Thankyou.

Mr Pointy

11,145 posts

158 months

Monday 22nd February 2021
quotequote all
Mopey said:
andySC said:
If the boiler is a Baxi Duo-Tec or similar close off the outermost of the 2 isolating valves underneath the boiler. I’d then turn off the power on the boiler & leave sat overnight. If the pressure drops with the valves turned off then the leak is on the boiler, as mentioned it’ll likely be the heat exchanger that has failed. If in the morning the pressure hasn’t altered open up the isolation valves, if the pressure drops straightaway the problem is on the system pipework.
Is this a DIY thing or need an engineer thing?
I have done the valves for refilling the boiler. I just wouldn’t want to make it worse.
It is indeed a baxi duo tec 28 I believe.

Thankyou.
You should be able to have a go yourself. The valves are on the tap rail connections - see page 11 of the manual:

https://www.freeboilermanuals.com/assets/pdf/baxi/...



You want to turn the one on left hand end (CH flow) & the one on the right hand end (CH return).

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
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Thanks. Then switch off the boiler. Do I need to place a bucket somewhere or simply watch the pressure overnight.
Will try this evening I think.

Sheepshanks

32,519 posts

118 months

Tuesday 23rd February 2021
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Mopey said:
My questions are; how much water are we talking about leaking?
Not an expert, but I think it's of the order of a couple of litres. Which is a reasonable amount if you're having to top it up twice a day.

Daughter's house has steady drip from a radiator tail and that was losing its pressure every few days.

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
quotequote all
Okay have tried and one of the plastic valves simply won’t turn! Is it safe to really go at it. Would hate to somehow flood the house!

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
quotequote all
Okay further update have taken the plastic cover off to get at the valve.
The valve on the right hand side so the heating return only turns clockwise even though the indicators appear to be for it to turn anti clockwise. This includes the plastic cover that was on it which would make it impossible to turn...
The left hand side one turns fine...
not sure if I should continue or just call someone out.

Edited by Mopey on Tuesday 23 February 11:45

Mr Pointy

11,145 posts

158 months

Tuesday 23rd February 2021
quotequote all
Mopey said:
Okay have tried and one of the plastic valves simply won’t turn! Is it safe to really go at it. Would hate to somehow flood the house!
Are you turning it the right way? It might not be the same way as the other one. You'll probably only break the plastic handle if it's really stuck. Maybe turn the heating on for a bit & see if the heat loosens it up, or give it a blast with a hot air gun/hair dryer.

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
quotequote all
Mr Pointy said:
Mopey said:
Okay have tried and one of the plastic valves simply won’t turn! Is it safe to really go at it. Would hate to somehow flood the house!
Are you turning it the right way? It might not be the same way as the other one. You'll probably only break the plastic handle if it's really stuck. Maybe turn the heating on for a bit & see if the heat loosens it up, or give it a blast with a hot air gun/hair dryer.
Thanks pointy. We were posting at the same time- does what I’ve written above make sense?

Mr Pointy

11,145 posts

158 months

Tuesday 23rd February 2021
quotequote all
Mopey said:
Mr Pointy said:
Mopey said:
Okay have tried and one of the plastic valves simply won’t turn! Is it safe to really go at it. Would hate to somehow flood the house!
Are you turning it the right way? It might not be the same way as the other one. You'll probably only break the plastic handle if it's really stuck. Maybe turn the heating on for a bit & see if the heat loosens it up, or give it a blast with a hot air gun/hair dryer.
Thanks pointy. We were posting at the same time- does what I’ve written above make sense?
Any chance of posting a couple of good pictures so we can see? The valves usually have a black plastic handle with a step in the base which means they only turn 90 degrees in one directon & back. They can be very stiff though - I have to use pair of pliers on mine sometimes.

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
quotequote all
Mr Pointy said:
Mopey said:
Mr Pointy said:
Mopey said:
Okay have tried and one of the plastic valves simply won’t turn! Is it safe to really go at it. Would hate to somehow flood the house!
Are you turning it the right way? It might not be the same way as the other one. You'll probably only break the plastic handle if it's really stuck. Maybe turn the heating on for a bit & see if the heat loosens it up, or give it a blast with a hot air gun/hair dryer.
Thanks pointy. We were posting at the same time- does what I’ve written above make sense?
Any chance of posting a couple of good pictures so we can see? The valves usually have a black plastic handle with a step in the base which means they only turn 90 degrees in one directon & back. They can be very stiff though - I have to use pair of pliers on mine sometimes.
Hi yes I will post a couple of pictures. That seems to be the problem. The way that the valve actually turns is the opposite way to which the plastic handle will allow because of the way it’s been made!

Mr Pointy

11,145 posts

158 months

Tuesday 23rd February 2021
quotequote all
Mopey said:
Hi yes I will post a couple of pictures. That seems to be the problem. The way that the valve actually turns is the opposite way to which the plastic handle will allow because of the way it’s been made!
That's a bit odd; I wonder if the handle was put on in the wrong orientation. Just keep track of where the valve is (open or closed) if you have the handle off.

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
quotequote all
Okay photos.
This is the one on the right hand side.
You can see that it wants me to turn it clockwise to switch it on. When off the valve only goes anti clockwise. There is zero way of putting the plastic on and turning anti clockwise. Which is why I’m a bit stumped.


Photo of all the taps for wider view.




So is it safe to say half turn anti clockwise and the logic would be that is then off... as it’s been heating the house when there is water in the system the problem is the pressure dropping.

Mr Pointy

11,145 posts

158 months

Tuesday 23rd February 2021
quotequote all
Mopey said:
Okay photos.
This is the one on the right hand side.
You can see that it wants me to turn it clockwise to switch it on. When off the valve only goes anti clockwise. There is zero way of putting the plastic on and turning anti clockwise. Which is why I’m a bit stumped.


Photo of all the taps for wider view.




So is it safe to say half turn anti clockwise and the logic would be that is then off... as it’s been heating the house when there is water in the system the problem is the pressure dropping.
If you're talking about the marking cast into the body I'm not too sure it's an guide to operation. Basically if the handle is in line with the body the valve is open & if it's at 90 degrees it's closed. It doesn't matter which way it turns 90 degrees.

Mopey

Original Poster:

2,388 posts

154 months

Tuesday 23rd February 2021
quotequote all
Okay. It’s impossible to turn it with the plastic on so I will do it with pliers on the valve itself tonight and see if that makes a change.
If pressure still drops it’s 100% the boiler.

Does it matter if my thermostat still calls for heat do I need to switch that off also?

And I’m assuming I pressurise before turning these two taps.

andySC

1,187 posts

157 months

Tuesday 23rd February 2021
quotequote all
Mopey said:
Okay photos.
This is the one on the right hand side.
You can see that it wants me to turn it clockwise to switch it on. When off the valve only goes anti clockwise. There is zero way of putting the plastic on and turning anti clockwise. Which is why I’m a bit stumped.


Photo of all the taps for wider view.




So is it safe to say half turn anti clockwise and the logic would be that is then off... as it’s been heating the house when there is water in the system the problem is the pressure dropping.
These valves turn 90 degrees. As they are shown in the pictures they’re in an open position (on). Turn them clockwise so that the black handle is “sideways” on as you look at it from the front. This is the closed position (off). Both valves will turn on/off in the same direction.