Internal view

Key to components

1. Fan pressure test point
2. Fan
3. Air/Gas adjustment screw
4. Gas valve
5. Inlet pressure test point
6. Boiler power switch
7. Flame indicator (green)
8. Cover for external wiring connections
9. Power and fault indicator (blue)
10. Boiler thermostat and reset knob
11. Flow connection 22mm compression
12. Drain point
13. Return connection 22mm compression
14. Service access point
15. Flue overheat thermostat
16. WB3 Heat exchanger
17. Manual vent point
18. Sensor boiler flow
19. Over-heat thermostat
20. Silicone tube (use to vent air from heat exchanger)
21. Removable top case for cleaning heat exchanger
22. Air/Gas manifold
23. Syphonic trap