DIY Doctor UK DIY Forums

I've just moved into a house which has a Bosch Wocester 240 combi boiler. Recently, a loud banging starts when the hot tap is opened (any tap, cellar, kitchen, bathroom or shower) It gets progressivly noisy as the flow rate increases. Sometines it will stop, other times it keeps going. Every so often you can run the tap and it's quiet.

Any ideas out there?

Thanks