TRV (valve body) vibrates when modulating central heating water flow

[StewartT]

Apologies if this is covered but I have an annoying and noisy problem. Having fitted a Drayton TRV to a newish valve body (approx 5 years use), I am getting a hammer action when the valve set point is close and I think the TRV has partially closed the valve to reduce water flow. Any ideas? Thanks

[PhilHornby · Accepted solution]

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@StewartT wrote:

I am getting a hammer action when the valve set point is close and I think the TRV has partially closed the valve to reduce water flow. 

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Is this a conventional, mechanical TRV - or a Wiser Electronic valve? 

The iTRV's only operate fully-open, or fully -closed (except when they are actually transiting from one state to the other, for a few seconds).

Either way I found a web site that seems to have a lot of info. regarding noisy valves:

https://westradiators.co.uk/blog/how-is-radiator-hammer-caused/