Old Glow Worm Spacesaver boiler - Cold water supply feed?

[RoninLee]

I am planning on swapping my old Glow-worm boiler for a combi boiler. This is part of a bathroom refurb project to get rid of the old airing cupboard which houses the hot water cylinder and cold water header tank.

I will be getting a pro to do the boiler swap, but I will be doing the bathroom refurb myself.

I am planning for the new pipework, but I cannot see where the current boiler takes the cold water supply from. There are 2 x large diameter pipes that go upto the hot water tank and 2 x 3/4 pipes that feed the central heating pump and radiators. Would the cold water supply feed into either of the aforementioned pipes somewhere?

Thanks

 

[45yearsagasman]

Yes it would. Most commonly the cold feed would be on the 28mm return pipe from the hot water cylinder. From there it would go up to the small expansion tank. Other places may be used, so just follow the 15mm pipe from the bottom of the tank and you will find the connection. This will not be mains pressure.

 

[RoninLee]

Yes it would. Most commonly the cold feed would be on the 28mm return pipe from the hot water cylinder. From there it would go up to the small expansion tank. Other places may be used, so just follow the 15mm pipe from the bottom of the tank and you will find the connection. This will not be mains pressure.

Thank you for the reply. I think I am missing something though. I take it the small expansion tank you mention is inside the boiler? I am not understanding which tank to look for to find the 15mm pipe you mention.

I only have a cold water header tank above the hot water tank.

I am still not understanding where the cold water feeds into the system. I can't see this in the airing cupboard (unless it takes place inside the hot water cylinder). Some off the pipework passes along a wall which has been plasterboarded and my fear is I might have to take this down to find the connection. But that would be a mains pressure would it not; as I can't see any feed from the cold water tank above the hot water tank going anywhere other than to the latter.

I'm a little lost and would appreciate any help. Thanks.

 

[45yearsagasman]

You may indeed have a primatic cylinder and therefore have no small expansion tank. It may well be stamped on the side of the cyl.