fan runs, pump runs, pressure switch makes but no ignition, have cleaned tubes and ensured reset button on ch stat is ok, electrodes not sparking. everything starts up as normal and goes through the start up procedure then goes to lockout, any ideas please am desperate
are you sure the fan switch has proved, if so then you should have power to the gas valve when ignition begins, if power to valve then probably ignition module on pcb, if no power to valve fan not proving
