In article ,
"Jason Judge" writes:
We' ve recently replaced an aging Gloworm cast-iron boiler with an Ideal
Response 120 combi. It works fine, apart from some noises.

Most of the radiators are fitted with thermostatic valves (only one radiator
is not). When a valve upstairs is on the point of closing, it seems to set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down a
little, so it is fully on or off, the vibrating stops.

This happens when valves are installed with the water passing
through in the wrong direction. Many valves are bi-directional
nowadays, but if yours isn't (should be an arrow on the valve
body), then it wants moving to the other end of the radiator
or turning round the other way (so the body is horizontal if
it's currently vertical), if the valve connections are
reversible for such mounting.

Another thought -- maybe the pump's dynamic pressure is rather
high. You haven't shut off the radiator with no TRV have you?
It might also be that the pump could be turned down a notch,
but that should really only be done if you can check the flow
through the boiler is still adequate.

--
Andrew Gabriel