Flexicom cx combination boiler - installation and service manual

15 Replacement of Parts15.1 GeneralReplacement parts that have associated components thatneed replacing on removal, i.e. ‘O’ ring, seals, gasket, etc.,will be supplied and should be fitted.Replacement of parts must be carried out by a competentperson approved at the time by the Health and SafetyExecutive.Before replacing any parts of the boiler it should be isolatedfrom the mains electric supply and the gas should be turnedoff at the gas service isolation valve on the boiler, seediagram 15.1.Unless stated otherwise parts are replaced in the reverseorder to removal.After replacing any parts always test for gas tightness and ifnecessary carry out functional test of the controls.13931Boiler AccessFor replacement of parts the front casing of the boiler willneed to be removed. To remove undo the two screws on theunderside of the front casing and lift off.If the appliance site situation has sufficient side clearancesthe side panels can be hinged sideways and removed to aidreplacement of parts.To hinge a side panel undo and remove the four screwssecuring each side panel to the boiler, two below and two atthe top.Draining of Boiler Heating CircuitDrain down the Heating Circuit of the boiler only, by closingthe heating flow and return isolating valves on the wallmounting jig. Attach a length of hose to the drain point andopen the drain valve, see diagram 15.1.After replacing parts, close the drain valve and remove thehose. Open the heating flow and return isolating valves andrefill, vent and pressurise the heating circuit, refer to section12.Check for leaks.Diagram 15.115584Draining of Boiler Hot Water CircuitDrain the Domestic Hot Water circuit by closing the cold-waterisolation valve on the wall mounting jig, see diagram 15.1.Open one or more hot water taps to drain the hot water circuit.After replacing parts open the cold-water isolation valve andslowly open a hot water tap to remove air. Close the hot watertap and check for any leaks.15.2 Igniter UnitFor access, refer to section 15.1.Remove ignition lead and electrical connections then removeigniter unit by removing two securing screws, see diagram13.9.15.3 Ignition LeadFor access, refer to section 15.1.Pull the spark plug style connector off the spark electrodeand the spade connector connected to the igniter unit, seediagram 13.6.Diagram 15.253