Hi, thanks for the replies Ive just got back from a short break. Is their a way to test the pressure from the fan? Reading my manual I found recently it asks "Is pressure difference at switch greater than 0.9 mbar" but dont know how i would test it, u-gauge maybe?
Alan
October 2008
check the items listed below for correct operation
(a) fan
(b) venturi
(c) venturi tubes
(d) air pressure switch
(e) ignition clectrode or leed
(f) pcb
universal heating ltd
October 2008
as the fan is running check that both the tubes from the exhaust fan to the pressure switch are sound and connected o.k if the pressure switch is making and it still does not fire up then you should suspect the control board PCB.
mr knowitall
October 2008
air pressure switch is in sequence between fan and ignition