On 04/11/2016 19:17, Tim+ wrote:
rick wrote:

Does your boiler have a similar system? I suspect that they've all moved
over to "single stage" ignition of the main burner but you never know...

Tim



Single stage I think ... no pilot flame ... just straight electrode for
ignition along with a flame failure detector.


I asked same Q ... on DIYnot forum ........ and have 2 guys who state
this is an obvious fault, simply fixed - known top all (except the 9
Gas Safe Techs who have been to my place presumably) but they are not
prepared to tell me what it is - even though I will not be touching gas
myslef.