11. Remove the assembly comprising the fan, Venturi, burner and gas
valve to access the inside of the heat exchanger.
SIRIUS THREE FS 200 and SIRIUS THREE FS 250
1. Switch off the mains supply to the boiler.
2. Close the gas inlet valve.
3. Close the valves on the heating circuits.
4. Access the internal boiler components.
5. Disconnect the power and command cables on the fan.
Fig.145
11
MW-2000787-02
Fig.146
MW-2000804-01
5
11 Maintenance
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