24 Classic LXFF, FF - InstallationINSTALLATION INSTALLATION42 COMMISSIONING AND TESTING(a) Electrical Installation1. Checks to ensure electrical safety should be carried outby a competent person.2. ALWAYS carry out preliminary electrical system checks,i.e. earth continuity, polarity, resistance to earth and shortcircuit using a suitable test meter.WARNING. Whilst effecting the required gas soundness test and purging air from the gas installation open all windows anddoors, extinguish naked lights and DO NOT SMOKE.(b) Gas Installation1. The whole of the gas installation, including the meter,MUST be inspected and tested for soundness, and purgedin accordance with the recommendations of BS. 6891.2. Purging air from the gas installation may be expedited byloosening the union on the gas service cock on the boilerand purging until gas is detected.3. Retighten the union and check for gas soundness.TO LIGHT THE BOILER1. Check that all the drain cocks are closed, and any valves inthe flow and return are open.2. Check that the gas service cock (B) is OPEN and the boilermains on/off switch is OFF.3. If the boiler output is to be set to minimum or mid, affix theappropriate indicator label supplied in the hardware pack tothe data badge, located on the controls support.4. Fitting the Boiler CasingDeluxe Model (LX) - Lift the boiler casing up to the boilerassembly, with the casing top angled forward. Hook the topedge of the boiler casing into the channel on the top of theboiler assembly. Swing the bottom of the casing down untilit is flush with the assembly. Lift the glass fascia and pull thesliding catch out to retain the glass in the upper position.Secure with the 2 captive screws. To improve access to thegas valve, remove the controls casing bottom panel byremoving its 2 retaining screws. Refer to Frame 44.Standard Model - The boiler casing must be refitted withthe controls pod casing attached for alignment purposes.Lift the boiler casing up to the boiler assembly, with the casingtop angled forward. Hook the top edge of the boiler casinginto the channel on the top of the boiler assembly. Swingthe bottom of the casing down and secure with the 2 captivescrews. To improve access to the gas valve, remove thecontrols pod casing. Release the controls pod front fixingscrews 3 turns only. Remove the pod by pulling it forward to43 INITIAL LIGHTING disengage from the keyhole slots. Refer to Frame 44.Note. Standard boiler only. If the Sealed System Unit isfitted remove the unit casing in order to inspect the topcasing seal.The casing must seat correctly and compress the sealingstrip to make an airtight joint. Visually check the sideseals but, if side clearances are limited, then check thatthe top and bottom edges of the casing are correctlylocated.5. Slacken the screw in the burner pressure test point (F) andconnect a gas pressure gauge via a flexible tube.6. Switch the electricity supply ON and check that all externalcontrols are calling for heat.7. Set the boiler thermostat knob (D) to position 6 and theboiler Mains on/off switch to ON. The fan will start. Afterthe fan has run for a few seconds the pilot solenoid valveshould open and the intermittent spark commence,continuing until the pilot is established. The main burnerwill then cross-light smoothly. If this sequence does notoccur, refer to the Fault Finding section.8. Test for gas soundness around ALL boiler gas componentsusing leak detection fluid.9. Operate the boiler for 10 minutes to stabilise the burnertemperature.10. The boiler is pre-set at the factory to its highest nominalrating but can be range rated to suit the system designrequirements. Refer to Table 2 (page 3). Remove the silverthreaded protection cap on the top of the regulator. Adjustthe main burner pressure adjuster (E) until the requiredmain burner pressure is achieved.11. Set the boiler mains on/off switch to OFF.12. Remove the pressure gauge and tube. Retighten the sealingscrew in the pressure test point.13. Turn ON and check for gas soundness at the pressure testpoint.14. Deluxe Model (LX)Refit the controls casing bottom panel and screws.Standard ModelRefit the controls pod and tighten the 2 front fixing screws.15. Deluxe Model (LX)Lower the glass fascia to its closed position.Standard Model.Close the pod door.LEGENDA Sightglass.B Gas service cock.C Inlet pressure test point.D Thermostat knobE Main burner pressure adjuster.F Burner pressure test point.H Boiler mains on/off switch.