There doesn't appear to be any pattern to it and it's usually when the heating/ hot water is not being used. it is now getting very difficult to reignite the pilot light - trying many times before this will remain on. Any suggestiosn?
Thanks
Stella

Stella Cox, October 2007

If the fan does not run slowly when just the pilot is lit then the flame will suffocate, until enough oxygen has made it into the combustion chamber it is going to be difficult to re light.

When you turn on the electricity to the boiler with no CH/hot water demand you should hear the fan start slow running.

If you dont hear the fan, then a faulty microswitch, dry joint or open circuit slow run resistor may be causing the fan not to run and remove pilot flame combustion products.

fred, November 2007

needs a new thermocouple. get someone qualified to fix it, not a diy job

jim, October 2007