Worcester 350 knocking

[martin917]

I have a 10 yr old Worcester 350. In the past 6 months I've had a constant rhythmical knocking that reverberates throughout the whole house, which only stops when I turn off the cold-water inlet to the boiler. Problem continues even with the electricity turned off. Service Eng from Nationwide has already replaced the hot water pump and says that the problem is not with the boiler. I have checked the whole house over and there are no leaks or tap problems. Central heating is fine. Please can you provide any assistance?

Thanks.

 

[Agile]

I dont really think that anyone can help you on a forum with so little information when a half competent fellow from some firm has already been there and failed to find the problem.

My advice is to get a competent person to diagnose the problem and depending on your relationship with them then if they are proved to have been incompetent then you can reclaim the cost of the competent person from them.

Tony

 

[chrishutt]

Water hammer? Could be fault on cold water isolating valve, although it's usually caused by float valves (ball valves in old speak).