Thank you in advance for any advice. My Combi boiler, a Biasi M90F.24S has developed a worsening, but intermittent DHW problem, whereby the boiler does not always light or CH stay lit when DHW is used (any/all hot taps same).
The boiler always lights fine when CH switched on and continues to work perfectly, until DHW is run, when the boiler "might" go out (but not always).
If CH has gone off because a DHW tap has been opened, then it always relights immediately when the hot tap is closed again.
When DHW not working the boiler pump/fans operate for a while, but there is no spark and eventually the boiler goes quiet. If the DHW does not light normally as soon as a DHW tap is opened, then it will not light until the tap has been switched off and left off for a few mins, after which time it "may" start working again.
Sorry for such long post, but wanted to descibe problem fully. I am not a DIYer, but would appreciate advice on likely cause and possible repair costs.
Thanks again
Ian
The boiler always lights fine when CH switched on and continues to work perfectly, until DHW is run, when the boiler "might" go out (but not always).
If CH has gone off because a DHW tap has been opened, then it always relights immediately when the hot tap is closed again.
When DHW not working the boiler pump/fans operate for a while, but there is no spark and eventually the boiler goes quiet. If the DHW does not light normally as soon as a DHW tap is opened, then it will not light until the tap has been switched off and left off for a few mins, after which time it "may" start working again.
Sorry for such long post, but wanted to descibe problem fully. I am not a DIYer, but would appreciate advice on likely cause and possible repair costs.
Thanks again
Ian
