British gas 330 boiler, simular to glow.worm hxi

[Cobra27]

Hi, I am a gas engineer seeking advice.

Boiler: British Gas 330 Heat Only

Symptoms:

Turn power off then on, fires at full rate then after 5 seonds drops to a really low rate as if its near temperature, take combustion cover off is stays at low rate, put it on and the fan fluctuates but still never reaches full rate.

Test Results:

1.Flow & return thermisters between 11.0 - 11.45
2.Combustion chamber clear, gaskets re-newed
3.Flue not obviously blocked
4.Fan Free, no signs of fan circuit board failier

Im saying its the gas valve, any sugestions?

Cheers Cobra27

 

[Dotty]

Cobra mate, welcome to the forums. Can you please send your gsr details to one of the admins, Dan, Dave or Mr Doberman? They'll give you access to the engineers section then. We can all discuss this freely and in private then.

Just don't want the public picking up any ideas on how to fix their own boilers you see.