23Henrad SE FF - Installation1. Remove the cardboard support aid from the flue and placesafely to one side.2. Fit the inner flue extension duct onto the inner flue duct.3. Fit the outer flue extension duct onto the outer air duct.4. Drill one 3.2mm (1/8") dia hole through the outer air duct.Do not drill the inner flue duct.5. Insert the self tapping screw provided to fix the air duct inposition.6. Repeat steps 1-5 if a second flue extension is required.7. Measure and mark the flue length required onto the flue,measuring from the groove near the terminal.8. To ensure a square cut, mark the flue all the way round.9. Cut to length using the cardboard support aid.10. Remove the cardboard off-cut and deburr the metal edges.33 FITTING THE KITINSTALLATIONINSTALLATION34 ELECTRICAL CONNECTIONSAppliances fitted with aREAR outlet flue : please refer to Frame 19Appliances fitted with a SIDE outlet flue : please refer to Frame 27WARNING. This appliance MUST be efficiently earthedA mains supply of 230 V ~ 50 Hz is required.The fuse rating should be 3 A.All external controls and wiring MUST be suitable for mainsvoltage. Wiring should be 3 core PVC insulated cable NOTLESS than 0.75 mm2 (24 x 0.2mm) and to BS. 6500, Table 16.Wiring external to the boiler MUST be in accordance with thecurrent I.E.E. (BS.7671) Wiring Regulations and any localregulations.Connection must be made in a way that allows completeisolation of the electrical supply - such as a double pole switchhaving a 3mm (1/8 ") contact separation in both poles, or a plugand socket serving only the boiler and system controls. Themeans of isolation must be accessible to the user afterinstallation.