Combi sudden pressure loss.

[Richb]

Hi, my 80 year old mum has a combi boiler that suddenly loses pressure. She lives 70 miles away and having problem diagnosing fault. It happens irregularly and suddenly so dont think it is leak. Expansion tank and prv has been changed by a local plumber. I think it might be dumping water out the prv, but never when i am there and have left tub under prv but it rained, tied freezer bag to prv, it split (could have filled and split).
Any ideas, I am thinking intermitant pump fault or thermostat causing system to overheat and dump pressure?
Any ideas welcome, this only happens about once or twice a week.
I am a qualified gas engineer but I mainly do site work so not experienced in fault finding.
Thanks.

 

[Neil Callaway]

When the expansion vessel was replaced was the pipe connecting it checked? I've had instances where the connection at the boiler end has been blocked. Might be worth a look.

 

[Richb]

When the expansion vessel was replaced was the pipe connecting it checked? I've had instances where the connection at the boiler end has been blocked. Might be worth a look.

I have removed this and blown through it etc, but thanks for your idea. I did wonder if dirt in system could be intermitantly causing such blocking.

 

[DevsAd]

It would certainly help, Rich, if someone could monitor what the pressure is doing as the boiler heats up - that would be a good indication.

But I understand your mum would find this difficult.

What make and model of combi is it? (Not that I'm thinking that'll help...!)

 

[Riley]

Really needs a gas safe engineer to take a look guys not something for the DIYer to be guessing at

 

[townfanjon]

Rich , if you are GS , email admin with your number .
Otherwise its against the rules to encourage somebody to remove a boiler case

 

[Neil Callaway]

Rich , if you are GS , email admin with your number .
Otherwise its against the rules to encourage somebody to remove a boiler case

Apparently have to post 10 times, I'm gas safe messaged Lou and Dan with GS number and card serial number, no response.

 

[townfanjon]

Apparently have to post 10 times, I'm gas safe messaged Lou and Dan with GS number and card serial number, no response.

I will have a go at summoning one of them lol
@Lou ,@Dan @ShaunCorbs

 

[Neil Callaway]

I will have a go at summoning one of them lol
@Lou ,@Dan @ShaunCorbs

Thanks

 

[Richb]

It would certainly help, Rich, if someone could monitor what the pressure is doing as the boiler heats up - that would be a good indication.

But I understand your mum would find this difficult.

What make and model of combi is it? (Not that I'm thinking that'll help...!)

Thanks for your replies.
I have checked pressure when visiting and behaves normal going from 1 bar cold to about 1.75 when hot.

 

[Richb]

Rich , if you are GS , email admin with your number .
Otherwise its against the rules to encourage somebody to remove a boiler case

Sorry did not mean to break any rules. I am gas qualified and registered through the company I work for. Dont do private jobs just new build installation. The work already done was by a local firm to my mum but they have failed to sort it and was just looking for suggestions before shelling out more money. I work for Cook and Harris Ltd reg no 1942

 

[Richb]

Thanks for your replies.
I have checked pressure when visiting and behaves normal going from 1 bar cold to about 1.75 when hot.

The boiler is an Ariston eco combi 27 mffi and is about 14 years old. Mum was charged about £800 to fit expansion vessel, if I new it was going to be that much I would have advised new boiler

 

[townfanjon]

The boiler is an Ariston eco combi 27 mffi and is about 14 years old. Mum was charged about £800 to fit expansion vessel, if I new it was going to be that much I would have advised new boiler

Robbing gits !!

 

[Neil Callaway]

The boiler is an Ariston eco combi 27 mffi and is about 14 years old. Mum was charged about £800 to fit expansion vessel, if I new it was going to be that much I would have advised new boiler

Hi Rich

It was a sealed system Ariston that I had to drill the crap out of the block where the flexible pipe connected, not that seems to be the case with yours.

 

[Richb]

Hi Rich

It was a sealed system Ariston that I had to drill the crap out of the block where the flexible pipe connected, not that seems to be the case with yours.

Thanks Neil. I do wonder if it might be the pathway to expansion gets temporarily blocked. Might try fitting external expansion vessel as there is room in cupboard.

 

[ShaunCorbs]

You rang town ?

 

[Lou]

sorted

 

[ShaunCorbs]

sorted

What about op Lou ?