Central Heating

Foghorn sound when drawing hot water

Anonymous user 09/03/2024 - 2.49 PM

CH/Plumbing question no. 1: I've read one post with this 'foghorn' issue but mine is a slightly different problem... My system is a CH boiler heating the rads and the hot water. I have a LARGE hot water storage tank in the airing cupboard but NO cold water storage header tank. (Is this what they call direct feed?) The problem only only started after the white expansion vessel above the hot water tank was replaced. And the foghorn effect ONLY occurs when drawing hot water while the timer runs the boiler to heat the water tank! I reckon its something to do with trapped air. If so, how do I clear it? Obviously I've changed the timer to heat the water in the middle of the night but I'd like a proper cure! Thanks in advance.