Spoke to Danfoss today having taken the fuel pump off. The shaft was a little on stiff side to turn and there was a slight squeak too. That's now been replaced along with the solenoid. And yes, the pressure has been set etc.
Incidentally, how hot should the solenoid get? I was surprised at...
The baffles, flue and everything would not suggest the boiler has been overfueled. The air/fuel mix was originally done in the old fashioned way (by my Oftec man!) ie, having set the fuel pressure to the correct setting (using a gauge) he decreased the air until smoke appeared and then increased...
It's a conventional flue. A gas analysis check has not been done recently. Could a rogue value cause this type of problem or are you both thinking the pump solenoid is more likely? I gather the whole thing can break down slowly but surely and was advised by Danfoss that they can be troublesome...
Oh this is getting tedious!
Having read reams and reams on the subject of intermittent oil burner problems I THOUGHT I had narrowed my problem down.
I found that the capacitor on the motor had leaked a small quantity of waxy substance which I imagined would signify it was giving up the...