Second expansion vessel from a previous boiler fault

[jh75]

Hi,

At my parents house they just had a new boiler fitted (from a free scheme). Due to some problems they've had (see other thread!) I've had a look around and noticed there was an expansion vessell on one the pipes in the cellar. I asked my parents and they told me that the expansion vessel was added on their n-2 boiler (i.e. not the previous boiler, but the one before that--- so it was done many years ago). I asked my parents about why it was installed and they said it was because the boiler at the time was faulty and the engineer said it would be too difficult to change the expansion vessel on the actual boiler so he added an additional one.

So since then they've had two boilers installed and the installers didn't remove or 'turn off' the extra expansion vessel. Just want to know if I should turn it off (via the isolation valve that's attached to it), or is it ok to leave it as is?

No politics in this thread please!

 

[muggles]

Why would you isolate it? It's not doing any harm. Leave it alone

 

[Aquaheat]

No harm in leaving it connected if anything it acts as a good secondary should there ever be a fault with the internal one on the new boiler. Just make sure that it's accessible and that the guys who carry out the annual service no it's there so that while checking the pre charge on the boilers vessel they can also check the pre charge of that one to ensure its still functional should you ever need it as a back up.

Jon

 

[Phill Peck]

Afaik you can't have too much expansion.
If I was installing and an additional vessel had previously been fitted I'd leave it in. Let's face it most boilers now have tiny vessels built in. So it will take some of the strain off that one and it will last longer.