Boiler losing pressure

Joined
15 Jan 2013
Messages
3
Reaction score
0
Location
Leeds
Country
United Kingdom
Apologies for length of this post but thought I'm better putting in as much detail as I can...

I have a Ferroli DOMIcompact F 23 B combi boiler (I know they are meant to be rubbish, I've been told this many times) also I have cover with British Gas and have had them out twice but the problem I have seems to persist.

The boiler loses pressure, for example today the pressure was at zero when I woke up so I put 1.2 bar of pressure in at 6am before work and didn't put the heating on, just used hot water for a bath and as I left for work my front door step was wet where it had leaked outside. (I now know it drips from the flue and not the overflow as would be expected)
When I returned from work at 5:30pm despite the heating not been on all day the pressure was at zero.

The British Gas engineers have told me that they believe there is a leak on the system which must be downstairs as if it was upstairs the ceiling would have come through by now. The trouble is, I have laminate flooring in my living room and tiled flooring in my kitchen - both are very difficult to take up and locate a leak though we put the kitchen flooring down 2 years ago and there were no leaks then and pipes are copper so can't see one suddenly developing.

The last time an engineer came he changed the pressure valve and also pumped up a balloon type thing that regulates the pressure or something? and he told me if it still loses pressure it must be a leak.

The only thing is why is it leaking from the flue and not the overflow? As to me this seems to be what is causing the problem.

I would really appreciate if anyone could give me any advise or help - would a leak sealer possibly solve the problem or does water leaking from the flue mean something else or does this just happen to be condensation as it is so cold outside?

Again thank you for reading this what probably looks like war and peace!
 
Sponsored Links
Just to add to this... I've been reading around and notice expansion vessel breaking seems to cause problems like I have, could this be the problem when 1st engineer said it needed pumping up which he did to 1 bar then 2 weeks later next engineer said it needed topping up again. Could it be that it needs replacing or does it sound more like I may have a leak?
 
Hi first of all the water coming out of your flue is condensate as you have a condensing boiler the flue should run back towards the boiler to stop this happening as by design the flue products will condense within the flue, this is not what is causing your pressure to drop.
If the expansion vessel was correctly re-pressurised and then required doing again two weeks later then that is likely to be your problem, if it is taking two weeks to deflate its more likely to be the Schraeder valve passing on the EV a very cheap and easy fix

Ian
 
Sponsored Links
Ah I see thanks for that, the flue was never cemented in properly when the boiler was fitted so British Gas have said it isn't to current standards though not unsafe, going to cement it when it's a bit warmer so the cement sets properly. Could that be why it drips instead of running back in? Also is there any way to isolate the downstairs to rule out a leak or would that not be possible? Does whats happening sound like expansion vessel? As I don't want to spend a lot on leak sealer if it will have no effect. Can pressure be lost totally due to a broken expansion vessel in the space of a matter of hours? Cheers again
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top