Alpha CB24 Flashing Indicator Neons, No Hot Water/Heating, please help?

alpha cb24
47-532-15
you say you have replaced the fan
was the replacement part number 1.017264?
installation manual
page 18
section 6.5
red & yellow neon lights flashing TOGETHER
blocked flue or fan fault
assuming flue is ok there are basically 3 components that could be causing problem
FAN [unlikely as it has already been replaced]
PCB
APS air pressure switch
if you're handy with a multimeter its possible to find the faulty component
FAN runs on 240 volts AC & fan coil has internal resistance of 35 ohms [cold]
APS runs on 24 volts DC
if this information doesnt make sense to you then you have no option but to get a competant gas engineer to fix boiler for you
APS 1.8396 £60
PCB 1.017118 £200

manwithnoname
May 2012