Yes its old concord wrs255. Hot water is turned on with the heating off. Problem the water is getting too hot and the rad's are getting warm upstairs. Can anypoint point me in the right direction what the problem could be?

Wayne, May 2009

thanks tom for the info. The strange think its only the upstairs but this is more than likely the gravity freed as you stated. I will give a thump and see if this resolves.

wayne, May 2009

Old systems worked on gravity hot water circulation and a pump on the heating.Usually if your radiators are getting hot and never did before it means one of two things.Either there is a non-return valve on the heating flow pipe from the boiler stuck open(can e freed with a thump if you can find it)...or the bad news ,there is a pipe fitted in the boiler which keeps the heating/hot water split(spreader tube).If this has gone its a new boiler or a controls upgrade.
As for the Hot water temp the only control you have is the boiler thermostat on the front of the boiler.Is this turned as low as possible?

Tom paris, May 2009