24cdi of combi fault

[huddster]

can anyone give me a quick hand with this fault-i have a 24 cdi of with ignition fault-slow flashing central heating light, when u reset pump runs and light flashes again any help would be great as i dont have the sequence of operation to hand

 

[Roger Welton]

CH slow flash is a burner lockout from memory, is it sparking? continuity across gas v/v solenoids?

 

[huddster]

no spark as soon as you reset, pump runs and back to ignition fault does anyone have sequence of operations?

 

[Roger Welton]

24CDi OF (discontinued March 2005) literature - Worcester, Bosch Group UK installer site

 

[fixter1]

is fan running????

 

[Roger Welton]

Open flue version

 

[jtsplumbing]

Have you tried switching of main power to boiler ? leave for 1min swirch back on then retry ! could be either -- spark electrode /control board / or gas valve, You need multimeter to check a few things out.

 

[fixter1]

spark electrode check spark gap,electrode lead

 

[Millsy 82]

Check the O/H stat, APS, Then fan.

It wont be gas valve spark electrode etc unless the fan has come on and APS has made.

 

[jtsplumbing]

Open Flue Millsy 82 No fan / aps

 

[Millsy 82]

Didnt see that bit should really read things properly,ignore me on that bit then

Check O/H stat, Just had a quick look through the online manual there is a flue stat aswell check that.

 

[huddster]

thanks for the replys, i got roped into looking at a boiler for a friend of a friend after work with only a screw driver and his by chance his multi meter- im still not 100% but i think its the pcb, main thermistor was in range-spillage stat ok , over heat stat had continuity- its the only thing left really, didnt check gas valve but not even getting to point of ignition-

as soon as boiler is reset even with no demand pump runs and lock out light flashes, almost as if the boiler is in frost protection