R
RobertC
Just had a new Potterton combi boiler installed and had the existing radiators single flow TRV’s replaced with bi directional TRV’s (one rad left without a TRV as per norm). When the heating reaches a specific setting one of the rads emits a vibrating hydro phonic noise which can be stopped by moving the TRV setting a fraction. However it returns or reappears on a different rad. I have had some success by turning the TRV settings higher and lowering the boiler temp but this is only a fudge and I am looking for a permanent fix. The plumber has no suggestions as he has only experienced this problem when single flow TRV’s are fitted to a new boiler.