I'm trying for central heating by turning control manually the indicating lights come on for central heating on demand & pump indicator light comes on then gas indicator comes on & I can hear ignition & it's trying to ignite but then red indicator light appears as tho it's cut out & burners won't ignite therefore no c/heating or hot water can u help me pls

Barry Beazant, October 2011

my vaillant boiler gos to f60

MR BAKE, November 2011

my boiler will not heat my house as it does not come on

colin, October 2011

If you can see the sparking through the window, then it can only be one of three things:

Pump flow switch (left of the pump) should 'break' when pump runs:

pcb not making GV relay

GV/solenoid not operating

Assuming you have no electrical testing knowledge, you will need to have these circuits checked.

Carefree, October 2011