What is this small White Vessel next to Worcester Boiler?

jefaz07

ThisIsWeird said:

What's the difference between the two types, I wonder? Apart from colour...
The white one uses non-toxic materials, I guess? But could it otherwise be used on a 'system'?

White has a rubber membrane inside and is used on potable water as you won’t get a rusty colour coming out of your taps. 

You could use it on a system I guess although they're generally more expensive. 

This one is on a cold feed, like I said, I’d suggest there was a tank there at one point. What with the reducing set, expansion vessel and holes in the floor. 

ThisIsWeird

jefaz07 said:

ThisIsWeird said:

What's the difference between the two types, I wonder? Apart from colour...
The white one uses non-toxic materials, I guess? But could it otherwise be used on a 'system'?

White has a rubber membrane inside and is used on potable water as you won’t get a rusty colour coming out of your taps. 

You could use it on a system I guess although they're generally more expensive. 

This one is on a cold feed, like I said, I’d suggest there was a tank there at one point. What with the reducing set, expansion vessel and holes in the floor. 

Thanks.
What do you mean by 'cold feed'?

jefaz07

ThisIsWeird said:

jefaz07 said:

ThisIsWeird said:

What's the difference between the two types, I wonder? Apart from colour...
The white one uses non-toxic materials, I guess? But could it otherwise be used on a 'system'?

White has a rubber membrane inside and is used on potable water as you won’t get a rusty colour coming out of your taps. 

You could use it on a system I guess although they're generally more expensive. 

This one is on a cold feed, like I said, I’d suggest there was a tank there at one point. What with the reducing set, expansion vessel and holes in the floor. 

Thanks.
What do you mean by 'cold feed'?

That pipe the expansion vessel is on, looks to me like a cold feed for an old unvented cylinder. 

It goes through a pressure reducing valve then to all cold outlets in the house so the pressure of HW and CW are equal at mixers. 

ThisIsWeird

I thought it was a pressure release valve, 'cos it appears to go off to a tundish. So I'm confused.

jefaz07

ThisIsWeird said:

I thought it was a pressure release valve, 'cos it appears to go off to a tundish. So I'm confused.

Haha yeah there is, you are right. I mean the bit before that, on an unvented setup the pressure reducing valve or inlet group (however you want to describe it) is before the PRV. 
I could be wrong, but off the one picture it looks like it could be to me. 

silvercar

We have a grey coloured one, with a pressure valve on it, but that’s on a conventional boiler.