Help required re Expansion vessel failure

[Tokyosi]

Morning Everyone.
I am looking for some help advice on who should be responsible for correcting a problem with my mothers boiler . It is a Grant Vortex Pro External Combi - not sure on the exact litrage but it is between 48 - 53.5 . It was installed less than a year ago but they only used for the first time June of this year ( the place was being renovated). It is in a two bedroom bungalow and runs 7 radiators + 2 bathroom radiators . The expansion vessel has failed and Grant are claiming that the boiler was too small for requirements hence it has failed and is not covered by guarantee . The plumber is saying "
The vessel at the time of fitting was deemed suitable, its charge was checked on commissioning and should work just fine.
The rate of expansion in the system for 7 radiators and the volume in the boiler with the static head of max 1m should be taken up easily with the factory fitted vessel"

My father has pointed out that ever since they started using it in June he has constantly had to go out and repressure the system .

I don't see that my parents should have to sort this out - whose responsibility is it?

Unfortuantely I really dont understand the workings - bars , litrage etc though I am beginning to get a better picture.

All help advice greatly appreciated

thanks

Simon

 

[Madrab]

No, it's not for your folks to sort out that's for sure.

Whoever installed the system is primarily responsible to ensure that the boiler and it's ancillaries install were fit for purpose. If there is a dispute over the design against actual capacity then I would asking for confirmation that the total system volume was calculated and can be shown on paper that it did not exceed the EV design capacity and therefore an additional EV wasn't required.

If that's not forthcoming then I'd be looking for someone else to do those calculations, then it can clearly be shown who's responsibility it is to correct.

 

[DaveHerns]

If the engineer specified the boiler and supplied it , it's down to him to rectify it .

 

[Tokyosi]

Thank you for your replies
Simon

 

[gigz]

9 rads in total ? Unless there's miles of 22mm pipework and the rads are absolutely massive i don't think the internal vessel would need upgrading. As already said, work out the system volume (your installer should help you) and relay that to the manufacterer. Has the installer checked/repressurised the vessel ?

 

[FiremanT]

Would an undersized vessel actually be damaged by being undersized? The PRV should open at 3 bar, so the vessel should not actually be subject to any ridiculously high pressures.
As Gigz suggests, it doesn't seem to be too big a system, altough the rads could all be large doubles.
Who said the EV is stuffed? Has the Mfr. actually called out to it? Has the installer been to it and checked the EV pressure.?
It does seem a bit strange - is Grant normally a difficult M'fer?

 

[Tokyosi]

Thanks again for all the replies , proving very helpful.

Simon

 

[leakydave]

On a Grant boiler the PRV opens at 2.5 bar.

 

[Agile]

I have never seen any evidence that Grant are particularly difficult.

But as suggested check the system volume and give the details to Grant.

Also I don't see any reason why an undersized EXV should fail.

Tony