Plumbing

Why do I only get two pints of hot water then cold.

Anonymous user 3 March 2024 - 3.16 PM

Hi,I have a gravity fed system ,with a back boiler in open fire and central heating as my heat sources. I get good heat in all radiators down and upstairs, but no matter what I try I only get two pints of hot water from hot tap then it returns to cold, the pressure in the tap does not drop, I have tried turning pipe stat up to heat tank more but it makes no difference, I'm reasonably familiar with the system though I can't see what I'm missing , I don't think it can be air.just wondering has anyone came up against this problem before or what am I failing to do, thanks