Have problem with my oil boiler operating properly - it fires up but only runs for about 20 seconds then cuts off and re-fires up after 20 seconds - and will run all day like that giving luke warm rads.
All pumps. stats working fine but fear it is the oil burner relay which is almost...
Read with interest your post on problem and noted you said your plumber has a honeywell R867A Protectorelay in his shed - I am looking for one desperately -does he still have it?