I have the same problem - was this problem the venturies? How do you clean them?
Craig
January 2010
Could be the fan venturies remove fan and venturies and clean them thoroughly ..even a tiny bit of verdigri will cause the air pressure to drop out on low burner pressure...trust me i had this quite a few times on this boiler
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix home heating systems.