ferroli modena 80e lockout?

Hi.when i call for dhw or ch boiler goes straight to lockout..i have a clicking sound from gas valve solenoid and then lockout(red light).If i disconnect lead to gas valve solenoid boiler sparks(it will not light due to lead being disconnected).Could this be the gas valve instead or the pcb(very expensive).1st thoughts are the pcb as when i hear the clicking sound surely that must mean the solenoid is working..Help very much appreciated