Alpha cd 18s boiler fault

[king of pipes]

Have a boiler playing up at the minute with ignition problems everything pointed to the gas valve monometer on the outlet proved it was not opening, the gas valve was replaced still nothing but have gas and a spark, checked the flue for restrictions, electrodes and rectifacation, heat exchanger is clean tubes connected, condense trap clear am i missing something here ? Cheers kop

 

[ShaunCorbs]

You checked pcb is sending voltage to the gas valve ?