Stelrad Group Boiler CX.140

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

Remove the purse clips securing the thermocouple to the pilot pipe

Remove the screw next to the thermocouple connections on the pilot burner

Undo the thermocouple connections at the pilot burner without damaging the electrode

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 and remove

Undo the two screws securing the pilot burner assembly to the pilot burner bracket

Undo the thermocouple and pilot gas pipe connections at the pilot burner assembly

CAREFULLY remove the pilot burner

Turn OFF the gas supply at the inlet gas cock

Switch OFF and DISCONNECT the electricity supply

Remove Main Boiler Thermostat Sensor

Remove the retaining clip from the thermostat pocket

Remove the earth connection and the two push-on leads connecting the controls box to the overheat thermostat

Remove the two screws securing the controls box to the side panels

Lift the controls box off the locating hooks

Ensure the system is cold and on full load with all temperature controls set at maximum.

Remove the screw in the manifold setting pressure test nipple and connect a suitable gas pressure gauge.

Light the boiler and allow it to operate for about fifteen minutes to stabilize the burners.

Check the manifold gas pressure.

Adjust the pressure to the figure shown in Table 1 for the appropriate boiler size.

Remove the dust cover over the adjuster.

Using a small screwdriver, turn the screw beneath clockwise to increase or anti-clockwise to decrease pressure.

Turn OFF the gas supply at the inlet gas cock

Switch OFF and DISCONNECT the electricity supply

Undo the two screws securing the controls box front panel

Lower the front panel to clear the location pegs

Carefully pull the front panel away from the controls box

Unplug the potentiometer lead from the 3-pin socket on the printed circuit board No. 1

Unplug the 6-pin L.E.D. lights plug from board No. 3