Look at the manual for circuit diagram.
I think the fan is supposed to stop running when the boiler has reached operational temperature. Pump keeps running (so the pin does not extract) to 'dump' heat to the radiators. After the anticycle timer has run out, if demand still in place, ignition sequence commences
Fan should run slow when boiler does not have heating or hot water demand
When was the boiler serviced last? Looked at your previous post on this boiler. You may want to look at page 2 of the manual to understand boiler operation a little better
Copied and pasted from earlier post......
The pilot was off two days ago
Pilot should not be off. If it is, then there is a defect that is popping the pilot.
I relighted the pilot, and it seemed working again when I tuned on hot water and central heating, but it just worked for 3 or 5 minutes, then stopped
Would be correct if heat demand satisfied.
no indication of temperature by the temperature guage, it dropped below the scale 0
Broken guage. Boiler operation not effected. Guage is only an indicator of heat. It does not alter boiler operation.
above the safety upper limit (1.5bar) just in few minutes
Safety limit is 3 bar when PRV ejects water
the boiler had been working well since it was repaired just over a year ago, which costed me a few hundreds quids
Only faulty parts should be replaced which do not cost arm and a leg, certainly not several hundred pounds. Even failed main heat exchanger or PCB replacement does not make the repair expensive in light of fact the boiler is a workhorse.
Looking at this post and previous, it seems the essential component missing is the boiler service. Look into it and you will have a boiler that operates as expected.
