Stelrad Group Boiler CX.340

Turn off the gas supply at the inlet gas cock

Switch off and disconnect the electricity supply

Remove the push-on tags and earth connection on the overheat thermostat body

Undo the two screws retaining the thermostat/piezo igniter bracket to the gas valve

Undo the two screws retaining the thermostat

Remove the retaining clip from the thermostat pocket

Remove the overheat thermostat phial

Turn OFF the gas supply at the inlet gas cock

Switch OFF and DISCONNECT the electricity supply

Remove Controls Box Front Panel

Remove controls box front panel as described in L.E.D. lights assembly

Store the front panel in a suitable place

Unplug wires from the overheat thermostat

Unplug the lead from printed circuit board No. 2

Ensure the system is cold and on full load

Set all temperature controls to maximum

Remove the screw in the manifold setting pressure test nipple

Connect a suitable gas pressure gauge securely

Allow the boiler to operate for 15 minutes to stabilize the burners

Verify the pilot flame conditions

Remove the cover cap from the adjuster screw

Replace the cover cap after adjustment

Turn OFF the gas supply at the inlet gas cock

Switch OFF and DISCONNECT the electricity supply

Remove the centre burner as previously described under Servicing

Unfasten the backnut retaining the electrode to the pilot burner bracket

Re-assemble in reverse order, checking that the spark gap is correct