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  5. Installation And Servicing Instructions

Worcester 26CDi Xtra Installation And Servicing Instructions

Manual is about: WALL MOUNTED CONDENSING COMBINATION BOILER FOR CENTRAL HEATING AND MAINS FED DOMESTIC HOT WATER

Summary of 26CDi Xtra

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    26cdi xtra wall mounted condensing combination boiler for central heating and mains fed domestic hot water installation and servicing instructions gc number 47 311 41 (n.G.) gc number 47 311 42 (l.P.G.) boiler output automatic modulating control to domestic hot water and central heating minimum 6.7 ...

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    1.1 gas safety (installation and use) regulations 1998, as amended, all gas appliances must be installed by a competent person in accordance with the above regulations. Failure to install appliances correctly could lead to prosecution. 1.2 the manufacturer’s notes must not be taken, in any way, as o...

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    An expansion vessel, pressure gauge and pressure relief valve. A by-pass for the central heating system. Temperature safety cut-out controls. A water flow regulator. A standard horizontal flue assembly giving flue lengths from 100mm to 1000mm. Optional extension flue kit to provide for flue lengths ...

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    80 50 80 50 80 50 80 50 non-cond. Condense non-cond. Condense. Non-cond condense non-cond condense 2.13 showers, bidets, taps and mixing valves hot and cold taps and mixing valves used in the system must be suitable for operating at mains pressure. Thermostatically controlled or pressure equalising ...

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    5 available pump head. Boiler output. Head min, flow rate temperature rise across heating flow kw btu/h metres feet l/min. Gal/min. And return 6.7 (22,860) 5.4 17.8 8.7 1.9 11°c (20°f) 7.2 (24,566) 5.7 18.8 5.1 1.1 20°c (37°f) 24.0 (81,888) 2.0 6.6 23.0 5.1 15°c (27°f) 26.0 (88,712) 3.5 11.6 18.6 4....

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    See figs. 2 and 3. 4.1 the appliance may be installed in any room although particular attention is drawn to the requirements of the current l.E.E. Wiring regulations bs 7671 and, in scotland, the electrical provisions of the building regulations applicable in scotland, with respect to the installati...

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    7 fig. 3. Appliance pipework connections screw driver required to operate valves. Valves shown closed. A b c d e f g 91 (a, b, c, d, and e) 61 110 (g) (f) (g) 85 a b c d e g f view on underside of appliance showing connections rear of appliance a ch flow = 62.5 b dhw out = 127.5 c mains cold water i...

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    See fig. 4 and 15. 5.1 the flue must be installed as specified in bs 5440:part 1. Important. The flue must be installed with an incline of 2 l / 2 ° (44mm per metre length) towards the appliance. See fig. 15. 5.2 the terminal must not cause an obstruction nor the discharge cause a nuisance. 5.3 if t...

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    See figs. 5, 6, and 7. 7.1 the system must comply with the requirements of bs 6798 and bs 5449. 7.2 the appliance must not be operated without the system being full of water, properly vented and pressurised. 7.3 the pressure relief valve operates at 3 bar (45lb/in 2 ). The discharge must be directed...

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    8.1 the following are general requirements and, if necessary, reference should be made to the local water company before fitting the appliance. 8.2 mains cold water inlet. Devices capable of preventing the flow of expansion water must not be fitted unless separate arrangements have been made. An exp...

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    11 fig. 9. Mains electricity connections. Strain relief clamp green/yellow brown brown blue green/yellow blue l 230v st12 n ns l r l s fig. 10. Wiring diagram. Fan overheat cut-off device flame sense electrode fan electrical connections black 1 white 4 red 3 air pressure switch spark electrode spark...

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    12 fig. 11. Functional flow diagram. Mains indicator on/of f switch st8 (l s ) st8 (l r ) st8 (n s ) st1 centre pin st15 pin l st1 pin l rel 1 rel 3 high low rel 4 pump fan (2 speed) st12 pin n optional link room thermostat t ransformer fuse f2 (1.25a slow) fuse f1 (2a slow) n n st12 pin l live in g...

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    13 fig. 12. 230 v room thermostat connections. Fig. 14. 230 v room thermostat and programmer connections. Fig. 13. 230 v programmer connections. N s l s st8 st8 st8 remove link neutral live switched live neutral neutral switched live live live switched live l r spare n s l s l r spare spare motor ne...

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    The appliance is supplied suitable for fitting to a sealed primary system only. Refer to fig. 15. Important two flue options are available: i) standard flue to suit rear or side flue installations where the flue length measured from the appliance casing to the outside of the wall is from 100mm to 10...

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    Rear and side installation drill or cut the flue duct hole horizontally through the wall. Refer to fig.17 for the minimum core drill size for various wall thickness. Note: the diameter of the hole takes into account the 2 1 / 2 ° incline of the flue system. Drill the six fixing holes 6.0mm deep for ...

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    Slide the appliance onto the pre-plumbing manifold ensure the three pegs are located correctly. Secure with the two m6 nuts and washers at the top and screw the appliance to the manifold at the bottom, using the three retaining caps and m6 bolts. See fig. 19. To access pegs and caps remove the botto...

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    Check the contents of the standard flue or the extended flue against their respective packing list. Remove all the packing from the ducts and terminal assembly. Note: the air duct is 100mm diameter and flue duct is 60mm diameter. Warning: the air and flue ducts are manufactured from aluminium and mu...

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    Flue terminal. F) drill through the holes in the flue terminal into the air duct with the drill provided. Fix the flue terminal temporary with the screws provided. Nb: when assembled correctly the flue duct will extend 44mm beyond the air duct. See fig. 23. G) undo the screws and ease the air duct c...

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    Check that all the water and gas connections have been tightened. If a facia mounted programmer is to be fitted follow the programmer instructions. Hinge down the facia as described in section 13.3 (c). Connect the mains electrical supply to the appliance at terminal st 12 (see fig. 9). Connect any ...

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    Remove the cabinet front panel. Check that the electrical supply and the gas service to the appliance are off. See fig 3. Check that all the water connections throughout the system are tight. Open the system valves at the appliance. See fig 3. Open all the radiator valves, fill the system and vent e...

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    Any programmer fitted on the appliance should be set up at this stage following the instructions sent with the programmer. The programmer will retain the setting for up to three weeks following an interruption in the electricity supply. Note: because the appliance is designed to operate at high effi...

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    Domestic hot water commence by opening a hot tap near to the appliance. Gradually close the hot tap and check that the burner pressure drops. Fully open the tap and check that the burner pressure rises. Fully close the tap and check that the burner goes off. The fan may continue running until the ap...

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    12.6 if an external programmer has been fitted which has a programmable domestic hot water facility then it is suggested that this be set to continuous or the equivalent. 12.7 tell the user, because the appliance is operating at high efficiency, a white plume of vapour will be emitted from the flue ...

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    Unhook the securing rods out of the locating holes in the combustion chamber sides. Ease the combustion chamber front and side assembly clear of the appliance. See fig. 32. And 35. (h) burner assembly hinge down the facia panel. Remove the inner casing cover and combustion chamber front and sides as...

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    When reassembling ensure the sealing washer located in the union nut is replaced. If the washer is damaged it must be replaced. Ensure the sealing grommets are fitted correctly and seal the inner casing. 13.4 servicing of components clean the fan any dust or fluff should be removed with a soft brush...

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    2. Air flow pressure switch. See fig.34. Check that the electricity supply to the appliance is turned off. Remove the cabinet front panel and hinge the facia down into the service position, as described in sections 13.3 (a) and 13.3 (c). Note the position of the tubes and electrical connections. Car...

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    8. Burner injector. See fig. 36. Remove the burner as described in section 13.3 (h). Unscrew the brass injector from the burner and discard. Fit the replacement injector and reassemble in the reverse order. Fit the burner with the replacement injector in the reverse order take care not to damage the...

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    12. Central heating sensor. See figs. 32 and 33. Check that the electricity supply to the appliance is turned off. Remove the inner casing cover as described in section 13.3 (b). Carefully pull off the two leads from the sensor. Pull off the sensor and spring retaining clip from the pipe. Discard th...

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    15. Pressure relief valve. See fig. 37 and 39. Check that the electricity supply to the appliance is turned off. Drain the central heating circuit as described in section 14.2 (a). Hinge the facia panel down into the servicing position as described in section 13.3 (c). Remove the bottom panel as des...

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    18. Water diverting valve micro switch assembly. See figs. 37 and 40. Check that the electricity supply to the appliance is turned off. Hinge down the facia panel into the servicing position as described in section 13.3 (c). To access the micro switch remove the bottom panel as described in section ...

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    Feed the pipe and sealing grommet clear of the inner casing. Retain all components and securing clips removed. Cut the plastic strap securing the expansion vessel to the appliance casing. Discard the strap. Remove the expansion vessel clear of the appliance. Disconnect the pipe from the expansion ve...

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    25. Secondary heat exchanger. See figs. 32, 33, 34, 35, 36, 37, 39, and 43. Check that the electricity supply to the appliance is turned off. Drain the central heating circuit as described in section 14.2 (a). The secondary high efficient heat exchanger is housed in a stainless steel box. The assemb...

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    Reassemble the appliance in the reverse order. Ensure all gasket seals and ‘o’ connections are made correctly. Open the valves fill and re-pressurise the system as described in section 11.1. 26. Condensate syphon. See fig. 37, 43 and 44. Check that the electricity supply to the appliance is turned o...

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    26 378 312 gas valve junkers bosch, type ce 426 1 8 747 003 366 0 78 375 695 burner – natural gas aeromatic, ref. Ac 23/05 3582 1 8 716 142 602 0 80 173 091 burner injector – natural gas stereomatic, type 7, 4.5mm dia. 1 8 716 140 208 0 81 375 697 spark electrode assembly buccleuch, ref. Be/3462/si ...

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    35 96 (ng or lpg) (ng or lpg) 109 201.

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    36 16. Operational flow diagrams main swit ch on gr een light on r oom thermost at and/or mains pr ogr ammer (or link) on and electr onic facia pr ogr ammer (if fitted) on and st13 link in and ch contr ol knob on central hea ting demand ch light on. Pump on. Fan on low/ ignition sequence. Burner lig...

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    37 main swit ch on gr een light on flow swit ch on (t op open) do mestic ho t w a ter demand (priority o ver ch demand) hw light on. Pump on. Fan on high/ ignition sequence. Burner light on. Ten second w ait gas v alv e off. (hw light still on. Pump still on) ov er temper atur e shut-down if w ater ...

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    38 within four minutes of last hot water demand and primary temperature above 80°c if heat demand has occurred in last 30 minutes if heat demand has not occurred in last 30 minutes run pump until primary drops to 80°c run fan until primary drops to 80°c if primary temperature still increases above 9...

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    39 no lights at all other faults not covered by above fail point c fail point b fail point e fail point j fail point k fail point a fail point d fail point f fail point g fail point h fail point i no green light (red lights work) no light (other lights work) light on constant (ch knob in off positio...

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    40 is the facia on/off switch turned on? `(clockwise) is there a 230v ac live supply across terminal st12 pins l and n has fuse f1 blown? Replace fuse and investigate cause. Suggestions: cable damage, connections to (or faults within) pump, fan, external 230v controls, transformer or board. Turn swi...

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    41 red diode is damaged. Replace control board. (section 14.3.23) is there a link at terminal st13 pins 1 and 2? Is there an electronic programmer at position st5 at right- hand end of board? Replace control board. (section 14.3.23). With ch control knob fully clockwise, does the boiler ignite and a...

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    42 boiler is running in “autofrost stat” mode. See section 17. Is the boiler in a very cold environment (less than 5°c)? Drop down the facia. Is the gas valve mode switch in the normal position? Fail point f no yes is the boiler fully water pressurised and is all air vented? Rectify fault. Fail poin...

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    43 remove front panel. Reset and restart the boiler. Can a flame be seen through the spy glass? Turn off boiler. Remove inner cover and combustion chamber cover. Is the sense electrode and lead in good condition and is gap correct. Remove multiway connector from board position st16. Is there continu...

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    44 remove multiway connector from board position st16. Test resistance across contacts 17 and 18 (yellow wires). Is it between 1 kohm and 30 kohm? Test resistance across contacts 12 and 13 (red wires). Is it between 1 kohm and 30 kohm? Replace control board. (section 14.3.23). Check or replace ch se...

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    45 does the fan run before the fault occurs? Turn off boiler. Is there continuity across the c and no terminals of the air pressure switch (where green wires are fitted)? Remove the fan connector from board position st1 and restart the boiler. Is there mains 230v across the centre (l) and left (n) t...

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    Yes yes 46 light indication during fault not covered by above details. Control board is likely to be wet or damaged or malfunctioning. Check for wet board or connections. Dry and re-use or replace control board. (section 14.3.23). Fail point k hot water temperature always too hot during a demand (no...

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    47.

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    This booklet is accurate at the date of printing but will be superseded and should be disregarded if specifications and/or appearances are changed in the interests of continued improvement. All goods sold are subject to our official conditions of sale, a copy of which may be obtained on application....