28 BOXER combination boiler - Installation and ServicingSERVICING40 SAMPLING POINT39 SERVICING SCHEDULETo ensure the continued safe and efficient operation of theappliance it is recommended that it is checked at regularintervals and serviced as necessary. The frequency ofservicing will depend upon the installation condition and usagebut should be carried out at least annually.It is the law that any service work must be carried out by aregistered CORGI installer.1. Light the boiler and operate for at least 10 minutes. Checkthe gas consumption (refer to table 2).2. Connect a suitable gas analyser to the sampling point onthe flue turret.For correct boiler operation, the CO/CO2 content of the fluegas should not be greater than 0.004 ratio.If this is the case, and the gas input is at least 90% of thenominal, then no further action need be taken. If not,proceed to Step 3 but see note above.3. Switch OFF the electrical supply.4. Remove the casing (refer to frame 41).5. Remove the expansion vessel and vertical protectionshield (refer to frame 43).6. Clean the main burner (refer to frame 46).7. Clean the heat exchanger (refer to frame 47).8. Check the main injector for blockage or damage (refer toframe 52).9. Check that the flue terminal is unobstructed and that theflue system is sealed correctly. Reassemble in the reverseorder.WARNING. Always turn OFF the gas supply at the gasservice cock, and switch OFF and disconnect the electricitysupply to the appliance before servicing.IMPORTANT.10. After completing the servicing or exchange of componentsalways test for gas soundness and carry out functionalchecks in 2 and 3 above.11. When work is complete the sealing panel MUST becorrectly refitted, ensuring that a good seal is made.12. Complete the service section in the Benchmark log book.Flue samplepointAir samplepointSERVICING