Unvented cylinder replacement

[industryspark]

Following on from my post a few days ago looking regarding my broken water cylinder i had a plumber come out to quote me to fix.

He pointed out what had happened. There is an expansion vessel (white coloured) actually inside the unvented cylinder. The expansion vessel had a big split in the top of it so has actually failed. I didnt get too close but it caused a reasonable leak into the kitchen below.

What is likely to have caused this part to fail? There is a pressure and temp relief valve on the cylinder that also looks like it has had some brown water come out from around the connection.

Strangely the hot water when turned on for an hour still heats up. Is it safe to do this as was never told that it wasn't.

 

[TimboTwo]

If the expansion vessel has ruptured, switch off all the water heating immediately, as the potential for devastating and possibly fatal consequences is huge.
There is nowhere for the expanding water to go, and if the tprv fails an explosion is very likely.

 

[muggles]

What make/model cylinder is it? I'd be very surprised if you need a whole new cylinder just because the expansion vessel has failed

 

[industryspark]

telford tornado stainless.

The system has a red expansion vessel on the outside which is at 1 bar, presumably this is the heating.
The cylinder has a white vessel inside it from what i could see which was split.

 

[JimCrow]

If the expansion vessel has ruptured, switch off all the water heating immediately, as the potential for devastating and possibly fatal consequences is huge.
There is nowhere for the expanding water to go, and if the tprv fails an explosion is very likely.

Except out the split in the expansion vessel .

 

[Registered Gas Man]

The vessel can be replaced. Will screw out and replacement will fit back in its place.

It takes a bit to get it turning as can't really get a grip on it.

 

[ianmcd]

you cant replace this yourself though