Baxi Boiler keeps losing pressure.

[Simon G]

Hello all,

My boiler is a fairly new installation (just under a year) and the pressure constantly drops at night after the central heating has been on. I only just re-pressurised the boiler last night to 1.4 bars and the boiler lost all of the pressure after being on for only a few hours during the evening.

The only leak that I can see is from a plastic pipe below the boiler that seems to lead outside which I’m pretty sure is the condensate pipe. Could this pipe be what’s causing the loss in pressure? Because I cannot see any other leaks.

I also would like to know if this thing is normal…
After re-pressuring the boiler and turning on the hot water moments ago, the boilers casing visibly expanded, which concerned me and I turned the water straight back off. Is this a normal part of operation as I have never seen the boilers casing physically expand with a thump.

Any help would be greatly appreciated as I don’t want to use my hot water right now.

 

[WC1]

Not normal. Suggest you switch off and call a suitable engineer.

 

[Simon G]

Not normal. Suggest you switch off and call a suitable engineer.

I know the boiler losing pressure isn’t normal but do you mean the expansion of the boilers casing is the main cause for concern?

 

[Deleted member 120897]

I know the boiler losing pressure isn’t normal but do you mean the expansion of the boilers casing is the main cause for concern?

Yes, stop using immediately until rectified. I’ve witnessed it a few times, but only once on a new boiler, which I called the manufacturer out under the warranty.

 

[Simon G]

Yes, stop using immediately until rectified. I’ve witnessed it a few times, but only once on a new boiler, which I called the manufacturer out under the warranty.

Thanks for the replies, I had the person that fitted the boiler come check it out and he said that the boiler is working completely fine and he replaced the leaking condensate pipe.

He thinks the leak may be underneath the floorboards in the house and not a problem inside the boiler itself.

The boiler expanding didn’t seem to happen though when he initially tested it after I told him about the issue.

He just said he’s never heard of anything like that and thought it was strange.

Do you guys think the boiler will be okay?

Thanks again.

 

[Deleted member 120897]

Hard to say, as we’ve not got eyes on site, not do we know much about it, eg make model. If it’s that young, I’d be looking at a warranty call, or least a call to manufacturer, let them make the decision.

 

[Simon G]

It’s a Main eco combi boiler, I think they’re part of Baxi.

 

[Deleted member 120897]

It’s a Main eco combi boiler, I think they’re part of Baxi.

Yes they are, so you could give them a call, and ask if they’d be able to attend a warranty call? I think it’s 5 years on their new boilers?

 

[WC1]

Even if its not under warranty see what they say about this "bulging boiler"

 

[Simon G]

Even if its not under warranty see what they say about this "bulging boiler"

I may have made it sound a bit worse than it actually is, the boilers casing only expanded for like a second or two and then made a thump when it went back to its original size.

The central heating and water has been on for about 3 hours and the boiler seems okay right now. Hopefully it stays that way. I appreciate the help 🙂

 

[Deleted member 120897]

It shouldn’t do it t all, unless there’s an issue.

 

[Simon G]

It shouldn’t do it t all, unless there’s an issue.

I’m not really sure what to do, because the plumber that fitted it has said it’s fine after coming and looking at it today and running some tests but you guys say it’s not.

Do you have any idea why the boiler casing could have expanded? Because the plumber that came round had no idea because he said he had never seen it before.

Thanks again.

 

[Scott_D]

Post some pictures of the boiler and pipes underneath and outside.
Give us a chance to help.

 

[Simon G]

Post some pictures of the boiler and pipes underneath and outside.
Give us a chance to help.

Here’s some images of the boiler and pipes. If you need any others I’ll happily take some more.

 

[ShaunCorbs]

Easy to know if it’s the system or boiler

Turn the left hand and right hand far valves off and turn the heating off for x amount of time eg for how long it takes to normally drop / loose pressure

 

[Simon G]

Easy to know if it’s the system or boiler

Turn the left hand and right hand far valves off and turn the heating off for x amount of time eg for how long it takes to normally drop / loose pressure

The plumber did that earlier but only for like 5-10 minutes and then said it’s not the boiler at fault.

 

[ShaunCorbs]

Does it normally drop within 5-10 mins every time you fill / notice it errored out ?

 

[Scott_D]

Where does the white pipe go?
Can you follow its route

 

[Simon G]

Does it normally drop within 5-10 mins every time you fill / notice it errored out ?

It’s usually overnight after the heating has been on. I will have to see if the pressure drops again tonight I guess.

But the other night when I posted on here and you replied, telling me how to re-pressurise the boiler. I did so up to about 1.3-1.4 mark and then the following morning it was at about 0.8.

 

[ShaunCorbs]

I’m guessing the system was cold when you topped the system up ?

 

[Simon G]

Where does the white pipe go?
Can you follow its route

It leads outside I’m pretty sure, here’s a picture of the two pipes, I think it leads into the black one.

The white pipe under the boiler did get replaced earlier on though by the plumber and it’s not leaked since.

 

[Simon G]

I’m guessing the system was cold when you topped the system up ?

I’m guessing the system was cold when you topped the system up ?

I think it was sitting at around 25 degrees Celsius when I topped it up, perhaps this was a bit too high? I have seen it drop to about 18-19 degrees when it’s not been on for a long period of time.

 

[ShaunCorbs]

No that’s fine does the black pipe go into the path ?

 

[Simon G]

Where does the white pipe go?
Can you follow its route

Also here’s the only two pipes that seem to lead outside from the boiler.

 

[Simon G]

No that’s fine does the black pipe go into the path ?

Yes, I think it goes straight into the floor outside.