Hiya this is a common problem with this boiler, the problem you have is the water flow switch is sticking,if that does not turn right off it will not allow the heating to start,...how to fix ?
When you drop the front panel (2 screws) , you will see 2 black rectangular boxes,one left, one right,(about 2 inches x 1 inch) the problem one is the left one , it is held on by a big circlip,prise it off and on the valve underneath you will see a spindle sticking out,if there is sign's of water then you must change the unit,as the washer will have split, but usually its just a case of dirt causing it to stick,put some vaseline or wd40 on the spindle and with a pair of pliers,pull it gently in and out,the re-attach the black box with the circlip,it is worth doing the other switch at the same time(on right near pump)hopefully that will solve the problem,..ps be sure to turn of the electricity to the boiler first.... good luck
Barry Richardson
December 2006
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