My boiler activates, lights and runs OK, but as soon as the gas lights there is a noisy vibration from behind the control panel and PCB. As best as I can figure it must be coming from the gas valve (assuming the grey square lump that has the gas pipe attached to it is the valve).
The gas flames are a healthy colour and their output is steady, the only problem is the noise and vibration.
This problem is intermittant - as all really annoying problems are!
Assuming the gas valve is basically some form of solenoid I would guess that it is failing to latch and juddering back and fro, but strange that it does not affect the gas flow.
Help please!!!!!!!!!

Mick Grant, February 2006

I had this problem 15 months ago and noticed that the
mains supply voltage was at the bottom end of tolerance (221-216V) - when I added 6v to the mains
to the boiler (with a transformer) the problem cured.
Subsequently, after my complaint, the supply voltage
went to the upper end (245-252V). But now the
problem has recurred. I dare not add any more volts -
I guess that the valve seat/seal is getting stickly
with old age (28 years).

John Chambers, March 2009

We had a similar problem initially diagnosed as the gas control valve but was in fact caused by a burnt out fan wiring dropping the solenoid voltage on the control valve

RL, July 2008

you are right about it being a solenoid ..however, if it is a white Rogers then this valve is no longer available - or very very expensive (live with it??)

Kevin, February 2006