Does a dual purpose expansion tank have a name?

[Jed43]

The expansion tank for my indirect feed hot water cylinder and the central heating bolier is in the loft. It seems to be just one tank - two linked compartments such that there is only one mains water feed , one overflow pipe and one expansion inlet pipe , one ball valve , but two outlets for gravity feed. Does this arrangement have an "official" name - seems hard to find a mention of it anywhere...

 

[ianmcd]

Your post is confusing , pics would be better

 

[Jed43]

Thanks for your reply .. would it help to say that they are two separate tanks linked by a side pipe connected from one to the other low down (not 2 compartments of one tank as I mistakenly thought). Each tank has a gravity feed outlet of its own ..

 

[muggles]

Could it be a Primatic cylinder? Not many left any more

 

[Jed43]

Aha! That rings a bell from a while ago when the plumber mentioned it.. cheers. I was thinking of replacing the hot water cylinder myself with plastic pipework...is that going to be tougher could \I ask? Isita special type of cylinder that has to be purchased?

 

[muggles]

They aren't available any more. System would require work to add an extra tank in the loft, and to convert the system to fully pumped

 

[Jed43]

OK thanks for the info.