My boiler goes to reduced burn, not on fault finding. All things appear to run OK. When powered off for 30 secs and switched back on the full burn resumes.
Just to update, it appears that reduced burn "so told by Glow worm" is to do with less than 19mbar at the boiler. Solenoids either work or not and as I've got pilot and full burn (at times) it's not that. It seems that after a period the boiler heat exchanger reaches a temp and things work till it cools down again.
John C
February 2012
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