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  5. Installation & Service Instructions Manual

Main Combi 24 HE Installation & Service Instructions Manual

Summary of Combi 24 HE

  • Page 1

    Installation & service instructions combi 24 this is a wall mounted combination boiler gas fired central heating unit. The boiler meets the requirements of statutory instrument “ the boiler (efficiency) regulations 1993 n o 3083” and is deemed to meet the requirements of directive 92/42/eec on the e...

  • Page 2

    2 building regulations and the benchmark commissioning checklist building regulations (england & wales) require notification of the installation of a heating appliance to the relevant local authority building control department. From 1 april 2005 this can be achieved via a competent persons self cer...

  • Page 3

    3 installer notification guidelines choose building regulations notification route contact your relevant local authority building control (labc) who will arrange an inspection or contact a government approved inspector labc will record the data and will issue a certificate of compliance corgi will r...

  • Page 4

    Legislation 4 codes of practice, most recent version should be used important - installation, commissioning, service & repair this appliance must be installed in accordance with the manufacturer’s instructions and the regulations in force. Read the instructions fully before installing or using the a...

  • Page 5

    5 contents 1.0 introduction 6 2.0 general layout 7 3.0 appliance operation 8 4.0 technical data 9 5.0 dimensions and fixings 10 6.0 system details 11 7.0 site requirements 14 8.0 installation 19 9.0 commissioning 24 10.0 completion 26 11.0 servicing 27 12.0 changing components 29 13.0 electrical 38 ...

  • Page 6

    1.0 introduction 6 1.1 description 1. The main combi 24 is a fully automatic gas fired wall mounted combination boiler. It is room sealed and fan assisted, and will provide central heating and mains fed domestic hot water. 2. The boiler is set to give a maximum output of 24.0 kw. 3. It is designed f...

  • Page 7

    7 2.0 general layout 2.1 layout 1. Air pressure switch 2. Expansion vessel 3. Burner manifold 4. Automatic air vent 5. Dhw plate heat exchanger 6. Circulation pump 7. Drain off point 8. Pressure relief valve 9. Optional integral timer position 10. Central heating system pressure gauge 11. Control pc...

  • Page 8

    3.0 appliance operation 8 note: all delay timers mentioned in 3.1 and 3.2 are overridden by domestic hot water demand. 3.1 central heating mode (fig. 4) 1. With a demand for heating, the pump circulates water through the primary circuit. At a pre-determined flow rate the central heating flow switch ...

  • Page 9

    9 4.0 technical data burner pressure (natural gas - g20) max rate min rate mbar 12.2 ± 0.5 2.5 ± 0.2 in wg 4.88 ± 0.2 1.0 ± 0.2 flue terminal diameter 100mm dimensions projection 95mm outercase dimensions casing height - 780mm overall height inc flue elbow - 980mm casing width - 450mm casing depth -...

  • Page 10

    5.0 dimensions and fixings 10 dimensions a 780mm b 345mm c 450mm d 107mm Ø min. E 200mm f 190mm g 143mm 360° orientation tube Ø 100mm d c b a e g f 65mm 65mm 65mm 65mm wall view from under the appliance gas inlet heating flow domestic hot water outlet cold water inlet heating return 130mm 165.7mm 95...

  • Page 11

    11 6.0 system details 6.1 information 1. The main combi 24 combination boiler is a ‘water byelaws scheme - approved product’. To comply with the water byelaws your attention is drawn to the following installation requirements and notes (irn). A) irn 001 - see text of entry for installation requireme...

  • Page 12

    6.0 system details 12 6.5 system filling and pressurising 1. A filling point connection on the central heating return pipework must be provided to facilitate initial filling and pressurising and also any subsequent water loss replacement/refilling. 2. There are connection points on the mains cold wa...

  • Page 13

    13 6.0 system details 6.8 domestic hot water circuit 1. All dhw circuits, connections, fittings, etc. Should be fully in accordance with relevant standards, the water supply (water fittings) regulations and the water bylaws (scotland). 2. Your attention is drawn to: for gb: guidance g17 to g24 and r...

  • Page 14

    7.0 site requirements 14 7.1 location 1. The boiler may be fitted to any suitable wall with the flue passing through an outside wall or roof and discharging to atmosphere in a position permitting satisfactory removal of combustion products and providing an adequate air supply. The boiler should be f...

  • Page 15

    15 7.0 site requirements 7.3 ventilation of compartments 1. Where the appliance is installed in a cupboard or compartment, no air vents are required. The appliance will run sufficiently cool without ventilation. 2. Minimum clearances must be maintained and the compartment should be large enough to h...

  • Page 16

    7.0 system requirements 16 7.6 flue 1. The following guidelines indicate the general requirements for siting balanced flue terminals. For gb recommendations are given in bs 5440 pt 1. For ie recommendations are given in the current edition of i.S. 813 “domestic gas installations”. 2. If the terminal...

  • Page 17

    17 7.0 site requirements fig. 20 100mm 1m fig. 19 flue trim adhesive seal fig. 17 fig. 18 7.7 flue dimensions the standard horizontal flue kit allows for flue lengths between 100mm and 1metre from elbow to terminal (fig. 17). The maximum permissible flue length is: 5 metres. 7.8 flue terminal trim 1...

  • Page 18

    7.0 site requirements 18 7.10 flue options 1. The main combi 24 can be fitted with flue systems as illustrated. 2. The standard flue is suitable only for horizontal applications. 3. Maximum permissible equivalent flue lengths are:- horizontal 5 metres vertical 4 metres vertical (twin pipe) 15 metres...

  • Page 19

    19 8.0 installation 8.1 initial preparation the gas supply, gas type and pressure must be checked for suitability before connection (see section 7.4). 1. After considering the site requirements (see section 7.0) position the fixing template on the wall ensuring it is level both horizontally and vert...

  • Page 20

    8.0 installation 20 8.4 fitting the boiler 1. Lift the boiler using the lower edges. Engage the slots at the top rear of the boiler on the wall plate hooks (fig. 23). 2. Ensure that the boiler is level and sits against the wall. 3. Take the two steel washers and remaining screws. Using the previousl...

  • Page 21

    21 8.0 installation 8.6 fitting the flue horizontal flue 1. The standard flue is suitable for lengths 100mm minimum to 1m maximum (measured from the edge of the flue elbow outlet). Rear flue: maximum wall thickness - 900mm side flue: maximum wall thickness - 870mm 2. Locate the flue elbow on the ada...

  • Page 22

    8.0 installation 22 8.6 fitting the flue (cont) important: if the flue length is greater than 1.5m the restrictor must be removed from the adaptor (fig. 29). 8. Take one of the rubber seals and position it on the boiler flue adaptor. Engage the flue elbow on the adaptor and pull the sleeve up so tha...

  • Page 23

    23 8.0 installation l 230 v selector / reset switch external controls n br b pump hydraulic differential pressure switch r r 3-way valve microswitch br bk safety overheat thermostat b b ntc sensor r r n br b fan n b pressure switch b br pcb b b br br r bk bk gas valve spark electrode flame sensing e...

  • Page 24

    9.0 commissioning 24 9.1 commissioning the boiler 1. Reference should be made to bs 5449 section 5 when commissioning the boiler. 2. Open the mains water supply to the boiler. 3. Open all hot water taps to purge the dhw system. 4. Ensure that the filling loop is connected and open, then open the hea...

  • Page 25

    25 9.0 commissioning out min pressure test point sealing screw gas valve central heating temperature control hot water temperature control fig. 42 fig. 43 fig. 44 2 1 0 4 3 bar reset burner on flame failure power on selector switch plastic protection cap modulator wire maximum rate adjustment nut mi...

  • Page 26

    10.0 completion 26 10.1 completion 1. Hinge the facia panel upwards and engage the securing screws. Refit the case front panel and tighten the screws (fig. 45). 2. Instruct the user in the operation of the boiler and system, explaining the operational sequence. 3. Carefully read and complete all sec...

  • Page 27

    27 11.0 servicing 11 .1 annual servicing 1. For reasons of safety and economy, it is recommended that the boiler is serviced annually. Servicing must be performed by a competent person. 2. After servicing, complete the relevant service interval record section of the benchmark commissioning checklist...

  • Page 28

    11.0 servicing 28 11.1 annual servicing (cont) 10. Remove the spring clips retaining the air box side baffle plates. Disengage the tabs on the baffles from the slots in the fan hood (fig. 52). 11. Undo the screws securing the fan hood assembly to the appliance back panel, and draw the fan and hood a...

  • Page 29

    29 12.0 changing components important: when changing components ensure that both the gas and electrical supplies to the boiler are isolated before any work is started. When the component has been changed turn the selector switch fully anticlockwise against the spring pressure to the reset position a...

  • Page 30

    12.0 changing components 30 12.3 heat exchanger (fig. 62) 1. Note the positions of the two sensing tubes on the outlet elbow and three wires on the fan motor and remove them (figs. 58 to 61). 2. Slacken the screws on the outlet sealing collar. Ease the collar upwards as far as possible. 3. Remove th...

  • Page 31

    31 12.0 changing components 12.5 injectors (fig. 64) 1. Remove the burner as described in section 12.4. 2. Undo the screws securing the injector manifold to the inlet elbow and remove the manifold. 3. Unscrew and replace injectors as required and examine the sealing gasket, replacing as necessary. R...

  • Page 32

    12.0 changing components 32 12.8 gas valve (fig. 66) 1. Undo the nut on the gas feed pipe under the boiler. 2. Completely undo the securing screws and hinge the facia panel down. 3. Disconnect the earth wire and pressure sensing pipe from the valve. Undo the screw securing the electrical plug to the...

  • Page 33

    33 12.0 changing components 12.11 pump - head only (figs. 68 & 69) 1. Drain the primary circuit and remove the socket head screws securing the pump head to the body and draw the head away. 2. Undo the screw on the pump wiring cover and remove the cover. Using a suitable flat bladed screw driver pres...

  • Page 34

    12.0 changing components 34 12.14 pressure gauge 1. Drain the primary circuit and undo the nut on the pressure gauge capillary (fig. 71). 2. Remove the timer cover and ease the timer wiring aside. Undo the screws securing the gauge retaining bracket (fig. 72). 3. Remove the bracket and gauge assembl...

  • Page 35

    35 12.0 changing components 12.17 pressure relief valve (fig. 78) 1. Drain the primary circuit. 2. Disconnect the discharge pipe from the valve. Using a suitable hexagon key undo the grub screw sufficiently to release the valve. 3. Note the orientation of the valve, rotate it and withdraw it from th...

  • Page 36

    12.0 changing components 36 12.20 plate heat exchanger (fig. 81) 1. Drain the primary circuit. 2. While supporting the heat exchanger undo the screws securing it to the brass manifolds. 3. Withdraw the heat exchanger upwards and to the left of the gas valve, taking care not to damage any wires or co...

  • Page 37

    37 12.0 changing components 12.21 diverter valve assembly (cont) ch pressure differential valve (fig. 84) 1. Remove the dhw pressure differential valve as described above. 2. From the brass diverter manifold undo the nut on the heating flow pipe. Remove the screw securing the diverter manifold to th...

  • Page 38

    13.0 electrical 38 optional timers pump gas valve air pressure switch pressure switch hydraulic differential temperature sensor selector switch on/off/reset fan control pcb flame electrode sensing microswitch 3-way valve m2 m5 m4 m1 m3 fa2 15 16 14 13 12 20 19 18 17 11 10 39 38 37 36 35 9 7 6 5 4 3 ...

  • Page 39

    39 14.0 fault finding carry out initial fault finding checks 1. Check that gas, water and electrical supplies are available at the boiler. Electrical supply = 230v ~ 50 hz. Ch water system pressurised to 0.5 bar when the boiler is cold. The preferred minimum gas pressure is 19.5mbar (natural gas), 2...

  • Page 40

    14.0 fault finding 40 domestic hot water - follow operational sequence turn selector to neon illuminated primary flow switch operated fan runs at max speed pump runs turn thermostat to max. Open dhw tap fully. Dhw flow switch operated primary water is diverted from ch system to dhw heat exchanger an...

  • Page 41

    41 14.0 fault finding fault finding solutions sections a to e is there 230v at: is there 230v at: main terminals l and n check electrical supply 1. No main terminal fuse replace fuse replace pcb neon illuminated 2. Yes selector terminals a & b and a & 3. Pcb - m1 connector terminals 9 & 10 check wir...

  • Page 42

    14.0 fault finding 42 check and correct if necessary 1. Electrical and pressure tube connections 2. Blockage of pressure tubes 3. Restriction in flue 4. Venturi no e replace air pressure switch gas at burner ensure gas is on and purged replace pcb replace gas valve neon illuminated pcb - m4 connecto...

  • Page 43

    43 14.0 fault finding check and correct if necessary 1. Flame sensing electrode and lead connections 2. Electrode position flame current should be 1 µa approx. Replace pcb replace pcb yes yes replace flame sensing electrode no yes ensure that mains input terminal l is live (230v) and n is neutral (0...

  • Page 44

    15.0 short parts list 44 short parts list key g.C. Description manufacturers no. No. Part no. 22 e66 383 fan 248001 23 393-497 pressure switch 247380 32 e66 393 heat exchanger 248016 41 e66 398 burner 248029 44 e66 402 injector - 1.28 ng 248210 44 injector - 0.77 lpg 248211 59 e66 408 electrode lead...

  • Page 45

    45 16.0 notes.

  • Page 46

    Controls to comply with the building regulations, each section must have a tick in one or other of the boxes time & temperature control to heating room t/stat & programmer/timer programmable roomstat time & temperature control to hot water cylinder t/stat & programmer/timer combi boiler heating zone...

  • Page 47: Service Interval Record

    Service 1 date engineer name company name tel no. Corgi id card serial no. Comments signature service 2 date engineer name company name tel no. Corgi id card serial no. Comments signature service 3 date engineer name company name tel no. Corgi id card serial no. Comments signature service 4 date eng...

  • Page 48

    Publication no. 5115807 - iss. 2 (05/2005) all descriptions and illustrations provided in this leaflet have been carefully prepared but we reserve the right to make changes and improvements in our products which may affect the accuracy of the information contained in this leaflet. All goods are sold...