32
British Gas 440 - 480 RD2 -
Installation & Servicing
SERVICING
54 HOT SURFACE IGNITER (HSI) REPLACEMENT
1. Remove the lower front panel and grille assembly.
Refer to Frame 47.
2. Remove the securing screw and lift off the control box
cover.
3. Unplug the HSI lead from the PCB and withdraw it from
the control box.
4. Remove the securing screw and withdraw the HSI from
the burner front plate.
5. Fit the new HSI and reassemble in reverse order.
6. Check that the position of the HSI relative to the burner
is correct.
7. Check the operation of the boiler.
1. Remove the lower front panel
and grille assembly. Refer to
Frame 47.
2. Remove the control box
cover.
3. Unplug the potentiometer
lead from the PCB and
withdraw it from the control
box.
4. Disengage the lead from the
retaining clips
5. Pull off the thermostat knob.
6. Remove the 2 screws
securing the potentiometer to
the control panel.
7. Remove the backnut securing
the potentiometer to the
bracket.
8. Fit the new potentiometer and
reassemble in reverse order.
9. Check the operation of the
boiler.
55 CONTROL THERMOSTAT POTENTIOMETER REPLACEMENT
SER
VICING