Text preview for : Buderus Boulter 500 24S System Boiler Service Manual.pdf part of Buderus 500 - 24/S [24/C] [28/C] Service manual Gas Wall Hung Boiler Condensing [02/2006 GB] - Part file 1/2, pag. 80
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7214 8900 02/2006 GB(EN)
For the installer
Servicing manual
Gas wall hung Boiler condensing Buderus 500 - 24/S Buderus 500 - 24/C Buderus 500 - 28/C
Please read thoroughly before attempting fault diagnosis
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The boiler meets the basic requirements of the appropriate standards and directives. Conformity has been substantiated by the proper documents which - together with the declaration of conformity - are filed with the manufacturer.
Subject to technical modifications! Constant development efforts may result in minor deviations in illustrations, functional steps and technical data. Updating the documentation If you have suggestions for improvement or have found discrepancies, please do not hesitate to contact us.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
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Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
box 1
List of contents
box 2
Preface
1 2 3 4 5 6 7 8 9
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Servicing manual user guide . . . . . . . . . . . 10 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Symptoms . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
These service instructions apply to: Buderus wall-mounted condensing gas boilers 500 - 24/S, 500 - 24/C and 500 - 28/C. Model: Type: Fuse rating: 500 28 C S C13(x), C33(x), C53(x), C73(x) GB/IE II2H3P 20 mbar, 37 mbar 1.25 Ampere slow blow
Power rating: 230 VAC, 50 Hz, IP X4D The boiler unit consists of the following components: Gas condensing boiler Maximum output is 28 kW Combination boiler (with integrated hot water supply) System boiler.
Important general instructions for use Only use the boiler in accordance with its designated use and the service instructions. Installation, maintenance and repair must be carried out by competent service engineers (e.g. CORGI registered). Only use the boiler in conjunction with the accessories and spare parts indicated in the installation, maintenance and service instructions. Other accessories and consumables may only be used if they are expressly provided for the designated use and if system performance and safety are not affected in any way. The boiler is suitable for connection to fully pumped, sealed water systems ONLY. Adequate arrangements for completely draining the system by provision of draining valves must be provided in the installation pipework. Pipework from the boiler is routed downwards as standard, but may be routed upwards behind the boiler using the wall spacing frame. Subject to technical modifications. As a result of our policy of constant development, there may be small differences between illustrations, functional steps and technical data.
G. C. Aplliance No. : Buderus 500-24/S Buderus 500-24/C Buderus 500-28/C 41-110-24 41-110-04 41-110-03 BENCHMARK' Log Book All Buderus gas fired boilers now include an installation, commissioning and service record log book. The details of the log book will be required in the event of any warranty work being requested. Please complete the appropriate sections on completion of the installation and commissioning.
Other manuals available for this boiler are: user manual; installation and maintenance instructions; wall spacing frame instructions.
REMEMBER: Please hand the log book back to the user.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
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1 General
General
Regulations and directives Timber Framed Buildings If the boiler is to be fitted in a timber framed building it should be fitted in accordance with the Institute of Gas Engineering document IGE/UP/7:1998 and BS 5440:1. Bathroom Installations This appliance is rated IP X4D. The boiler may be installed in any room or internal space, although particular attention is drawn to the requirements of the current IEE (BS.7671) Wiring Regulations and, in Scotland, the electrical provisions of the building regulations applicable in Scotland, with respect to the installation of the boiler in a room or internal space containing a bath or shower. If the appliance is to be installed or serviced in a room containing a bath or shower then, providing water jets are not going to be used for cleaning purposes (as in communal baths/showers), the appliance can be installed or serviced in Zone 3, as detailed in BS.7671. Compartment Installations A compartment used to enclose the boiler should be designed and constructed especially for this purpose. An existing cupboard or compartment may be used, provided that it is modified for the purpose. In both cases, details of essential features of cupboard/ compartment design, including airing cupboard installation, are to conform to the following: BS 6798 (No cupboard ventilation is required - see 'Air Supply' for details). It is not necessary to have a purpose-provided air vent in the room or internal space in which the boiler is installed. Neither is it necessary to ventilate a cupboard or compartment in which the boiler is installed, due to the low surface temperatures of the boiler casing during operation; therefore the requirements of BS 6798, Clause 12, and BS 5440:2 may be disregarded. The permanent clearances required are: in front: 8 mm below: 21 mm right side: 8 mm left side: 8 mm above: 21 mm The position selected for installation MUST allow adequate space for servicing in front of the boiler. See table below: in front: below: right side: left side: above: 350 mm 180 mm 8 mm 8 mm 200 mm
box 3
It is a requirement that all gas appliances are installed and serviced by a CORGI registered installer in accordance with the regulations. Failure to service appliances correctly could lead to prosecution. It is in your own interest, and that of safety, to ensure the law is complied with. It is a requirement and in your own interest, and that of safety that this boiler must be serviced by a CORGI registered installer, in accordance with the relevant requirements of the current Gas Safety (Installation and Use) Regulations, The Building Regulations, current I.E.E. Wiring Regulations and the relevant British Standard Codes of Practise. Detailed recommendations are contained in the following British Standard Codes of Practice: BS. 5440:1 BS. 5440:2 BS. 5449 BS. 5546 BS. 6798 BS. 6891 Flues (for gas appliances of rated input not exceeding 70 kW). Ventilation (for gas appliances of rated input not exceeding 70 kW). Forced circulation hot water systems. Installation of gas hot water supplies for domestic purposes (2nd. family Gases). Installation of gas fired hot water boilers of rated input not exceeding 60 kW. Low pressure installation pipes.
BS. 7593: 1992: Code of practice for treatment of water in domestic hot water central heating systems. IGE/UP/1b Tightness testing and purging domestic sized gas installations.
Health and & Safety Document No. 635. The Electricity at Work Regulations, 1989. The manufacturer's notes must not be taken, in any way, as overriding statutory obligations. The design and construction of the Buderus wall-mounted condensing gas boiler conforms to the basic specifications listed in the European directive governing gas-fired appliances 90/396/EEC, and with respect to EN 625, EN 483 and EN 677.
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NOTE: Observe the corresponding technical rules and the building supervisory and statutory regulations when installing and operating the system. WARNING! Keep the burner-control unit housing CLOSED when working on water-bearing components. NOTE: It is mandatory to clean and service the system once a year. This includes an inspection of the entire system to see if it is in full working order. Defects and faults must be eliminated immediately. NOTE: When instructions aren't followed, warranty expires. NOTE: Condensing boilers work more efficient if the CH flow/return temperature is as low as possible.
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In addition, sufficient space may be required to allow lifting access to the wall mounting bracket. Wall-mounted condensing gas combi boilers must only be operated with Buderus purpose made gas systems, which are certified for this type of boiler.
Buderus Ltd. · http://www.buderus-domestic.co.uk
We reserve the right to make technical modifications
4
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
General
box 4 Observe the relevant standards, regulations and legislation of the country or region of final use.
A A A A A
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Hazard definitions and abbreviations
Hazard definitions DANGER: Indicates the presence of hazards that will cause severe personal injury, death or substantial property damage. WARNING: Indicates the presence of hazards that can cause severe personal injury, death or substantial property damage. CAUTION: Indicates presence of hazards that will or cause minor personal injury or property damage. NOTICE: Indicates special instructions on installation, operation or maintenance that are important but not related to personal injury or property damage.
CAUTION! Use this boiler for its intended purpose only. DANGER! Notes relating to the heating system water. Thoroughly flush the system before it is filled with water. Use only untreated water or water treatment product such as Sentinel X100 to fill and top up the system. For more information about Sentinel call 0151 420 9563. When using water treatment, only products suitable for use with Buderus heat exchangers are permitted (e.g. Sentinel X100). Your warranty is at risk if an incorrect water treatment product is used in conjunction with this appliance. For more information, contact Buderus Technical Product Support Department. It is most important that the correct concentration of the water treatment product is maintained in accordance with the manufacturer's instructions. If the boiler is used in an existing system any unsuitable additives MUST be removed by thorough cleaning. BS.7593:1992 details the steps necessary to clean a domestic central heating system. In hard water areas, treatment to prevent lime scale may be necessary - however, the use of artificially softened water is NOT permitted. Under no circumstances should the boiler be fired before the system has been thoroughly flushed. Do not use artificially softened water. Only plastic pipework containing a polymeric barrier should be used. It is allowed to use copper for the first 600 mm. NOTE: Notes relating to domestic hot water The domestic hot water service must be in accordance with BS 5546 and BS 6700. The boilers are suitable for connection to most types of washing machine and dishwasher appliances. When connecting to suitable showers, ensure that: a. The shower is capable of accepting mains pressures and temperatures up to 65 °C. b. The shower is ideally thermostatic or pressure balancing. Where temporary hardness exceeds 150 mg/litre, it is recommended that a proprietary scale reducing device is fitted into the boiler cold supply with the requirements of the local water company. CAUTION! Provision must be made to accommodate the expansion of DHW contained within the appliance, where a back flow prevention device is fitted BS. 67989: §5.4.3.
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Abbreviations AV = BCT = BDV = CB = CH = CHF = CHR = CT = CWDO = DHW = DV = E = L = LSV = MCW = N = JB = PL = Prog = PRV = RT = RV = T = TRV = WC = ZV = Air Vent Buderus cylinder thermostat Buderus diverter valve Connection Block Central Heating Central Heating Flow Central Heating Return Cylinder Thermostat Condensate water drainage outlet Domestic Hot Water Diverter Valve Earth Live Lock Shield Valve Mains Cold Water Neutal Junction Box / RTH Relay Permanent Live Programmer Pressure relief valve (safety valve) Room Thermostat ModuLink 250 RF Receiver Timer Thermostatic Radiator Valve Wiring Centre Two Port Zone Valve
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Safe handling of substances No asbestos, mercury or CFCs are included in any part of the boiler and its manufacture.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
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box 5
Buderus
General
Technical specifications
Unit kW 500-24/S 5.7 28.5 (with external tank) 5.7 23.0 5.7 28.5 500-24/C 6.0 24.0 500-28/C 5.7 28.5
Hot water capacity (combination boilers)
Rated thermal load for CH Rated thermal load for preparing DHW Rated heating capacity for system temperature (modulating from 30° to 100°) Heating curve 75/60 °C Heating curve 40/30 °C Seasonal efficiency (SEDBUK) for natural gas for propane Maximum gas consumption, hot water/tank Maximum gas consumption, heating Boiler efficiency (40/30°C) (lower value/upper value) (full load) Boiler efficiency (40/30°C) (lower value) (partial load) Boiler efficiency (40/30°C) (upper value) (partial load) Boiler efficiency (75/60 °C) (lower value/upper value) (full load) Boiler efficiency (75/60°C) (lower value/upper value) (partial load) Chimney loss with burner shut down (standby heat loss) at nominal thermal load Hot water circuit
kW kW
5.7 23.0 5.7 23.0
5.7 23.0 5.7 28.5
kW kW % % m3/h m3/h % % % % % %
5.3 22.0 6.0 24.0 90.3 92.3 3.02 2.43 104 / 104 107 96.3 95.7 / 86.2 94.6 / 85.2 1.2
5.3 22.0 6.0 24.0 90.3 92.3 2.43 2.43 104 / 104 107 96.3 95.7 / 86.2 94.6 / 85.2 1.2
5.3 22.0 6.0 24.0 90.3 92.3 3.02 2.43 104 / 104 107 96.3 95.7 / 86.2 94.6 / 85.2 1.2
T at residual head of 200 mbar
Maximum flow temperature Permitted system pressure Expansion vessel Capacity of expansion vessel Admission pressure of expansion vessel Plate heat exchanger DHW flow rate at 35 °C rise Supply pressure of hot water Adjustable DHW temperature Pipe connections Condensate outlet CH flow/return (compression fitting) MCW inlet / DHW outlet (compression fitting) Gas on installation frame (compression fitting) Pressure relief valve Flue-gas connection Type of flue-gas connection (model) Ø Flue gas pipe / combustion-air inlet
°C °C bar
<20 80 1.0 3.0
<20 80 1.0 3.0
<20 80 1.0 3.0
l bar
7.5 1.0
7.5 1.0
7.5 1.0
l/min bar °C
9.4 0.8 - 10.0 40 - 60
11.7 0.9 - 10.0 40 - 60
Ø mm Ø mm Ø mm Ø mm Ø mm
21.5 22.0 15.0 22.0
21.5 22.0 15.0 22.0
21.5 22.0 15.0 22.0
15 mm (adapter supplied with boiler)
C13(x), C33(x), C53(x), C73(x) mm 60/100 (accessory)
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
6
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
General
box 5
Buderus Flue-gas readings Condensate water quantity, natural gas, 40/30 °C Exhaust-fume mass-flow rate Full load Part-load Exhaust-fume temperature, full load Heating curve 75/60 °C Heating curve 40/30 °C Exhaust-fume temperature, partial load Heating curve 75/60 °C Heating curve 40/30 °C CO2 full load, natural gas standard test gas G20 CO2 full load, natural gas standard test gas G31 propane Standard emission factor NOx Standard emission factor CO Flow pressure available for use Electrical specifications Mains connection voltage Electrical protection rating Electrical power consumption, standby Electrical power consumption, partial load Electrical power consumption, full load Dimensions and weight of boiler height × width × depth Weight without casing Weight with casing Gas Category of gas as per EN 437 for GB Gas injector Ø natural gas H (G20) Gas injector Ø propane P (G31) Venturi article number Natural gas H mm mm mm kg kg 780 × 460 × 330 30 33 780 × 460 × 330 31 34 W W W Vac 230 (50 Hz) IP X4D 4 88 110 l/h g/s g/s °C °C °C °C % % ppm (mg/kWh) ppm (mg/kWh) Pa 1.6 10.6 4.3 77 55 60 35 9,2 10.3 <30 <22 75
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Technical specifications
Unit 500-24/S 500-24/C 500-28/C
780 × 460 × 330 31 34
II2H3P 20 mbar, 37 mbar (natural gas H and propane P) 4.45 3.45 423.072A 4.45 3.45 423.072A 4.45 3.45 423.072A
Delivered ready for operation, adjusted to Wobbe index 14.1 kWh/m3 (with reference to 15 °C, 1013 mbar), applicable to Wobbe index range 11.3 to 15.2 kWh/m3. Markings on gas classification plate: Configured category: G 20 - 2E - 20 mbar Deemed suitable for use with propane after inspection by a registered Corgi heating engineer. Markings on gas classification plate: Configured category: 3P G 31_30-50 mbar. UP 15-50 5 minutes 30 - 40 seconds 1 minute 5 minutes 30 - 40 seconds 30 seconds 1 minute 5 minutes 30 - 40 seconds 30 seconds 1 minute
Propane P
Other items Pump Pump over-run time: Heating system default adjustments External cylinder Plate heat exchanger (ECO) Plate heat exchanger (warm start) After service mode
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
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box 6
General
Overview Buderus 500
11 12 1 13 2 14
3
15 16 17 18 19
4 5 6 7 8
20 21 22
23
24 9 25 26 10 27 28
29
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
8
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
General
box 7 Item 1: Item 2: Item 3: Item 4: Item 5: Item 6: Item 7: Item 8: Item 9: Key to terms Ionisation electrode Glow ignitor Automatic air vent Safety sensor Clamp for heat exchanger cover Plate heat exchanger Condensate trap Flow NTC sensor DHW flow regulator box 8
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General points
WARNING! DANGER OF FATAL ACCIDENT FROM EXPLOSIVE FUMES If you smell gas There is a danger of explosion. No naked lights. No smoking. DO NOT use a naked light to detect possible leaks. DO NOT operate any device that is likely to produce sparks. DO NOT operate electrical switches of any kind (including telephones, plug-in devices and doorbells) Shut off the gas supply at the main valve. Open doors and windows. Warn other occupants of the building (but DO NOT use the house intercom or doorbells). Contact the gas supplier from a telephone located outside the building. If you detect an audible gas leak, evacuate the building immediately, prevent other persons from entering, and notify the police and fire service immediately (from a telephone OUTSIDE the building).
Item 10: Pressure gauge Item 11: Concentric flue gas adaptor Item 12 Fan Item 13: Frame Item 14: Gas/Air unit Item 15: Sight glass Item 16: Gas valve Item 17: Heat exchanger Item 18: Gas supply pipe Item 19: Identification plate of boiler Item 20: Air silencer tube Item 21: Flue gas pipe Item 22: Flue gas safety temperature limiter (STL) Item 23: Pump 15-50 Item 24: Pressure relief valve discharge pipe Item 25: Syphon Item 26: Identification plate showing gas category Item 27: Connection block Item 28: DBA control panel Item 29: RTH converter / junction box
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WARNING! DANGER OF FATAL ACCIDENT due to electric shock
CAUTION! General information on maintenance work.
USER INSTRUCTIONS Instructions for optimum usage, correct adjustment of the boiler and other useful information.
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CAUTION! Use eye protection, inhalation protection, hearing, gloves, shoes etc. on the right time.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
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Servicing manual user guide
Servicing manual user guide
box 9 This document consists of various sections. These in turn contain subsections/boxes in the form of text or tables. Subsections/boxes inside text and tables are identified by a small grey box. Each subsection/box is assigned its own identification number. These subsections/boxes are divided into operating steps. If an operating step involves the taking of a yes/no decision, the right-hand side of the table indicates which subsection / operating step you should proceed (cross reference).
Section
Cross reference to subsection or operating step Subsection/box
6
box 24
step 28 step 29
Diagnosis
Check the actuation of the servomotor of the internal three-way valve, see box 186. Does the servomotor of the internal three-way valve start up correctly? Yes: No: step 30 step 31 box 43
step 30 step 31 step 32
Replace the servomotor of the internal three-way valve, see box 191. Check the power supply cable of the internal three-way valve, see box 192. Is the power supply cable of the internal three-way valve in good condition? Yes: No:
box 42 step 33 box 43
step 33 step 34 step 35
Replace the cable loom (or the affected part thereof). Check the movement of the servomotor of the Buderus 24V AC external three-way valve, see box 212. Does the servomotor of the Buderus 24V AC external three-way valve operate correctly? Yes: No:
step 36 step 39
step 36 step 37
Check to ensure that the the Buderus 24V AC external three-way valve has been fitted correctly, see box 228. Has the Buderus 24V AC external three-way valve been fitted correctly? Yes: No: step 45 step 38 box 43
step 38 step 39 step 40
Install the Buderus 24V AC external three-way valve correctly, see box 228. Check to ensure that the Buderus 24V AC external three-way valve is actuated correctly, see box 213 and box 229. Does the Buderus 24V AC external three-way valve actuate correctly? Yes: No:
step 41 step 42 box 43
step 41 step 42 step 43
Replace the servomotor of the Buderus 24V AC external three-way valve, see box 218. Check the wiring of the Buderus 24V AC external three-way valve, see box 221. Is the wiring of the Buderus 24V AC external three-way valve in correct condition? Yes: No:
step 47 step 44 box 43
step 44 step 45 step 46
Replace the wiring of the Buderus 24V AC external three-way valve. Check the drive mechanism of the Buderus 24V AC external three-way valve, see box 222. Is the drive mechanism of the Buderus 24V AC external three-way valve working correctly? Yes: No:
box 42 step 47 box 43
step 47 step 48
Replace the internal components of the Buderus 24V AC external three-way valve, see box 225. Check the wiring of the Buderus 24V AC external three-way valve between the connection box or moving plug-and-socket connection and the control panel as per box 288.
box 25
On combi boiler supply: hot water available, but no heating operation. On system boiler supply: no heating operation. Hot water may be available, but no heating operation. step 1 step 2 Check to ensure that the power supply cable to the RTH converter/Junction box has been installed correctly, see box 286. Is the 230V connection to the RTH converter/Junction box fitted correctly? Yes: No: step 3 step 4 Correctly attach the switch live to terminal 1 and Neutral to terminal 2 on the 230V connector, see box 286. Disconnect black leads from terminals 1 & 2 on the back of the DBA and test for continuity between the two leads. No continuity check S/L and N connections are made correctly and that there is 230v between the two. Replace RTH converter/Junction box. Continuity reconnect the cables to terminals 1 & 2 and check the connections between the terminals and the DBA. box 43 step 4 step 3
We reserve the right to make technical modifications
Buderus Ltd · http://www.buderus-domestic.co.uk
24
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2005
Operating step number Explanation of this subject starts in this box. The following boxes can be relevant as well.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
10
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Operation
3 Operation
3
box 10
Operation
box 11 3 4 5 6
General points
2
1
7
1
The central boiler can be run from the DBA control panel (item 1).
item 1: item 2: item 3: item 4: item 5: item 6: item 7: Mains switch 0/1 Reset button Service button Display Menu button Adjusting arrow UP Adjusting arrow DOWN
You can navigate through the menu structure of the central boiler using the service button, reset button, C-button and D-button (item 2, 3, 5, 6 and 7) and the display (item 4), box 12 to 14.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
11
3
box 12
step 1 step 2 step 3 step 4
Operation
Normal Operation menu
[24] Current CH flow temperature, in °C. See also box 20.
Keep the D-button pressed.
[00] current DHW flow rate, in litres per minute
Continue with Normal Operation menu ? Yes: No:
step 6 step 5 step 1 step 4
step 5 step 6 step 7
Release the D-button. Keep the C-button pressed.
[0h] Operating code. See also box 20 In this case: The boiler is ready for operation. No current heat requirement. Service Mode menu (no hot water is available during service-mode operation) [24] Current CH flow temperature, in °C. See also box 20.
Activate service mode? Yes: No:
box 13
step 1 step 2
step 3 step 1
step 3 step 4
Press the A-button once.
,24] As soon as the spanner symbol on the left-hand side of the display and the flame appear, the boiler will run for 30 minutes in service mode. The maximum CH flow temperature (as configured in the "Settings" menu) applies in this case.
Briefly press the C-button. Partial-load service mode [lo] is activated. Check the gas/air ratio and ionisation current. Adjust the gas/air ratio as required. See box 233 and box 143. Exit partial-load service mode? Yes: No:
step 5 step 6
step 7
step 8 step 6
step 8 step 9 step 10
Press the A-button once. Briefly press the C-button. Full-load service mode ,hi] is activated. Check the working gas input pressure, or analyse the exhaust gas accordingly box 230. Exit full-load service mode? Yes: No:
step 11
step 12 step 10 step 1
step 12 step 13
Press the A-button once, or wait for service mode to expire (after 30 minutes). Service mode is deactivated.
box 14
step 1 step 2
Settings menu
[24] Current CH flow temperature, in °C. See also box 17.
Open "Settings" menu? Yes: No:
step 3 step 1 step 4 step 5 step 9
step 3 step 4
Press the E-button once. Is boiler a combination boiler with warm start ? Yes: No:
step 5 step 6
[pr# ( H / I ) Configured hot water mode. As soon as [pr# is displayed, you can verify the current hot water mode, or adjust it as required. See also box 18.
Adjust configured hot water mode ? Yes: No:
step 7 step 8
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
12
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Operation
box 14
step 7
3
Settings menu
Use single or multiple operation of the D- and C-buttons to activate and disable hot water mode. [pr# ( H ): Hot water mode to ECO, [pr`( I ): Hot water mode to warm start. Press the E-button once.
step 8 step 9
[60) As soon as the DHW temperature (in °C) appears on the display [60), you can read the current DHW temperature, or adjust it as required. See also box 18.
Yes: No:
step 10 Adjust DHW temperature ?
step 11 step 12
step 11 Lower: lower the DHW temperature with the D-button. Higher: increase the DHW temperature with the C-button. step 12 Press the E-button once. step 13 [pr' ( K / L ) Configured heating mode. As soon as [pr' is displayed, you can verify the current heating mode, or adjust it as required. See also box 18. step 14 Adjust configured heating mode ? Yes: No: step 15 Use single or multiple operation of the D- and C-buttons to activate and disable heating mode.
step 15 step 16
[pr. (K ): Heating mode on, [pr; (L ): Heating mode off.
step 16 Press the E-button once. step 17 [80. Configure CH flow temperature, in °C. See also box 18. As soon as [80. is displayed, you can verify the current CH flow temperature, or adjust it as required. step 18 Adjust CH flow temperature ? Yes: No: step 19 Lower: lower the CH flow temperature with the D-button. Higher: increase the CH flow temperature with the C-button. step 20 Has at least 10 seconds passed without a button being pressed and/or was mains supply interrupted ? Yes: No: step 21 Press the E-button once. step 22 Any adjustments that you have made will now be confirmed.
step 19 step 20
step 22 step 21 step 1
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Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
13
4
4 Function
Function
Boiler Functions
Start phase
box 15
step 1 step 2 step 3
Turn the mains switch to "ON". Turn the operating switch on the DBA control panel of the boiler to position "1" (ON) see also box 11. Is a 3-way valve fitted? Yes: No:
step 4
Is the 3-way valve set to "hot water mode"?
Yes: No:
step 4 step 6 step 5 step 6
step 5 step 6 step 7 step 8
The Buderus 24V AC external 3-way valve is turned to "heating mode" in 7.5 seconds, while an internal 3-way valve is turned to "heating mode" in 2 seconds.
,00{ The display on the DBA control panel of the boiler is checked (maximum of one second). [24] Current CH flow temperature, in °C. See also box 20. C [0u] The boiler begins to warm up. Start of pre purge phase.
The fan runs for 15 seconds at about 60 % of maximum speed. Checking phase
step 9
Has the pre purge been completed correctly?
Yes: No:
step 11 step 10
step 10
Deal with fault. The error code, which is now displayed, can be found in box 20. Deal with the fault. Operating phase
step 11 step 12
C [0h] Operating code. See also box 20. The boiler is ready for operation. No current heat requirement.
Start of pump over-run time via the heating system. The pump over-run time: via the heating system, factory-adjusted to 5 minutes; via the external reservoir, set to 30-40 seconds; via the plate heat exchanger (ECO), set to 30-40 seconds; via the plate heat exchanger (warm start), set to 30 seconds; after service mode, 1 minute.
step 13
Has the pump over-run time expired?
Yes: No:
step 14
Is the boiler set to warm start for hot water and/or is an external storage-type water heater connected?
Yes: No:
step 15
Is the plate heat exchanger triggered and/or is the temperature in the external storage-type water heater at least 5 °C below the temperature set at the DBA control panel? Is there a current heat requirement from the (room) temperature controller?
Yes: No: Yes: No:
step 16
step 17
Is the current CH flow temperature lower than 7 °C (frost protection)?
Yes: No:
step 18 step 14 step 15 step 16 step 28 step 16 step 46 step 19 step 62 step 18 step 23 step 20 step 28 step 21 step 46 step 22
step 18 step 19
The pump stops. Has the pump been out of use for more than 24 hours? Yes: No:
step 20
Is the plate heat exchanger triggered and/or is the temperature in the external storage-type water heater at least 5 °C below the temperature set at the DBA control panel? Is there a current heat requirement from the (room) temperature controller?
Yes: No: Yes: No:
step 21
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
14
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Function
box 15 Boiler Functions
Yes: No: step 23 The pump is run for 10 seconds in order to prevent it from seizing up. step 24 Have 10 seconds elapsed? Yes: No: step 25 Is the plate heat exchanger triggered and/or is the temperature in the external storage-type water heater at least 5 °C below the temperature set at the DBA control panel? step 26 Is there a current heat requirement from the (room) temperature controller? Yes: No: Yes: No: step 27 Is the current CH flow temperature lower than 7 °C (frost protection)? step 28 The symbol "H" or "I" for hot water mode on the DBA control panel display lights up. step 29 C [0c] The fan runs at 49 % of capacity. The 3-way valve turns to the hot water setting for two seconds. The glow ignitor is activated for two seconds. step 30 C [0l] Ignition phase: The gas valve is opened. The glow ignitor is activated for one second, followed by alternating half-second periods of inactivity and activity until five seconds have elapsed. step 31 Does the ionisation current exceed 1.4 µA (microamperes) within 5 seconds? step 32 C [=h] The boiler is in hot water mode. If there has been a power cut: The startup load on the boiler is 49% for the first 13 seconds for the purposes of flow monitoring. It is then increased or decreased accordingly. The symbol " G " lights up. step 33 Is the temperature in the plate heat exchanger higher than the temperature entered via the DBA control panel? Yes: No: step 34 Is the CH flow temperature 46 °C higher than the preset DHW temperature and/or higher than 93 °C? step 35 C [0y] The gas valve is closed and the burner is shut down. step 36 The symbol " G " goes out. step 37 The fan stops after 30 seconds. step 38 Is the CH flow temperature lower than the preset DHW temperature plus 35°C? Yes: No: step 39 The gas valve is closed and the burner is shut down. step 40 The symbol G goes out. step 41 Start of pump over-run time via the cylinder. Start of pre purge phase (10 seconds). step 42 The fan stops. step 43 C [0h] The pump stops. step 44 The 3-way valve turns to the heating mode setting for two seconds. The symbol "H" or "I" goes out. step 45 Is there a current heat requirement from the (room) temperature controller? step 46 The symbol K lights up. step 47 C [0c] The fan runs at 49 % of capacity. The pump is started up. The glow ignitor is activated for seven seconds. step 48 C [0l] Ignition phase: The gas valve is opened. Yes: No: Yes: No: Yes: No: Yes: No:
4
step 22 Is the current CH flow temperature lower than 7 °C (frost protection)?
step 62 step 23 step 18 step 25 step 28 step 26 step 46 step 27 step 62 step 24
step 32 step 72
step 39 step 34 step 35 step 32
step 29 step 38
step 46 step 19
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
15
4
box 15
step 49
Function
Boiler Functions
Yes: No:
Does the ionisation current exceed 1.4 µA (microamperes)) within 5 seconds?
step 50 step 72
step 50
[-h] The boiler is in heating mode. The symbol G lights up. The startup load on the boiler is 49% for the first 13 seconds for the purposes of flow monitoring. It is then increased or decreased.
Is there a heating requirement from the (room) temperature controller? Yes: No:
step 51
step 52
Is the heat system flow temperature 6 °C higher than the target setting? (The target setting is entered at the DBA control panel if room-temperature adjustment is required)
Yes: No:
step 52 step 57 step 53 step 50
step 53 step 54 step 55 step 56
C [0y] The gas valve is closed and the burner is shut down.
The symbol G goes out. The fan stops. Is the CH flow temperature 6 °C lower than the target setting? The symbol "K " goes out. Yes: No:
step 47 step 53
step 57 step 58 step 59 step 60 step 61 step 62 step 63
C [0h] The gas valve is closed and the burner is shut down.
The symbol " G " goes out. Start of pump over-run time via the heating system. The pump over-run time via the heating system is 5 minutes. Start of the post purge phase of fan (10 seconds). The fan stops. The symbol "K " lights up.
step 13
C [0c] The fan starts up. The pump is started up.
The glow ignitor is activated for seven seconds.
step 64 step 65
C [0l] Ignition phase: The gas valve is opened.
Does the ionisation current exceed 1.4 µA (microamperes) within 5 seconds? Yes: No:
step 66 box 36 step 68 step 67
step 66 step 67
C [-h] The symbol " G " lights up. The boiler is in heating mode.
Is the current CH flow temperature higher than 15 °C? The symbol "K goes out. Yes: No:
step 68 step 69 step 70 step 71
C [0h] The gas valve is closed. The burner is shut down. The symbol G goes out.
Start of pump over-run time via the heating system. The pump over-run time via the heating system is 5 minutes. Start of the post purge phase of fan (10 seconds). The fan stops.
step 13
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
16
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Symptoms
5 Symptoms
5
box 16
Display indication
Display icons
Key to display indication
F G H I J K L
box 17
Display readings
Service mode Ionisation signal (flame monitoring) Hot water mode "ECO" setting or hot water requirement Hot water mode "warm start" setting or hot water requirement Standby, hot water mode to "warm start" Heating mode or heating requirement Summer operation, no heating mode, hot water only Display readings
Key to display reading Unit Range Factory default setting
[24]
box 18
Button
Current CH flow temperature Control-panel settings
Display Setting Key to display setting
°C
[30]
[80]
Unit
Range
1x A
<24] [lo] [hi]
Service mode Service mode, partial load Service mode, full load End service mode (or wait for 30 minutes) % % 25 100
C
1x A C 1x A
E E E E [//]
1)
[pr# [60) [pr' [80.
= flashing
Hot water mode Only applies to combi boilers 1) DHW temperature Heating mode CH flow temperature
°C °C
H = Hot water supply to ECO
I = Hot water mode to warm start
40 60
K = Heating mode ON L = Heating mode OFF
30 80
When it appears on the display at a system boiler, please connect a link between terminal 3 and 4 on the back side of the DBA control panel (hot water cylinder sensor) or make sure that the hot water cylinder sensor is fitted securely. Displaycodes
box 19
Normaly you see the current CH flow temperature. By pushing the "C"-button you will see the current operation code. Blocking: The boiler stops heating and will wait until the blocking is solved. Locking: Displaycode is blinking and also a blinking wrench "F" appears. The boiler stops heating and the pump is still running. The only way to stop the locking is by pushing the reset "B" button.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
17
5
box 20
Symptoms
Display codes
Display indication
z
C C C C C C
Display code
Key to display code
Reset Other symptoms required?
No indication on DBA control panel display.
Diagnosis
box 21 box 21 box 22 box 23
[//] [//) [0h]
Standby Standby
Hot water mode to "warm start". No (or insufficient) hot water, radiators, convectors, etc. may be heated without current heat requirement. Applies to boilers with hot water supply, hot water available, no heating operation. Applies to boilers without hot water supply, no heating operation.
[0h] [0h] :-h. :=h) [0a]
Standby Operating phase: The boiler is in heating mode. Operating phase: The boiler is in hot water mode. The symbol " G " lights up. Operating phase: Pump over-run time via the external cylinder/hot water heater. The symbol " G " is off. Operating phase: The switch optimisation program is activated. This program is activated if there is, more frequently than once every 10 minutes, a heating water requirement from an RC or ON/OFF control signal. This means that the boiler cannot be restarted until at least 10 minutes have elapsed since initial startup of the burner. Pre-operative phase: The boiler prepares for burner startup whenever a heating requirement or hot water requirement arises. Ready for operation: The boiler is in ready mode. There is a current heat requirement, but too much energy has been supplied. Standby for operation: The boiler is in ready mode. There is no current heat requirement. Ignition phase: The gas valve is activated. Startup phase: The boiler starts up after activation of the mains power supply or completion of a system reset. This code is displayed for a maximum of 4 minutes. Operating phase: The flow sensor has detected that the current CH flow temperature is higher than the temperature entered at the control unit, or that it is higher than the CH flow temperature calculated according to heating requirements, or that it is higher than the CH flow temperature calculated for the purposes of hot water supply. Fault: The flow sensor or safety sensor has detected that the current CH flow temperature is higher than 95°C. Fault: The flue-gas STL (fume-monitoring device) has detected a temperature higher than 105°C. The flue-gas STL is opened. Fault: The flow sensor and safety sensor have, after burner startup, not detected any temperature increase in the heating water, or they have determined that the temperature difference between The flow sensor and safety sensor is too high. No
1)
Applies to boilers with hot water supply, hot water available, no heating operation.
box 24
The heating circuit is warmed up without a heat requirement. Pump over-run time: Heating system factory default setting = 5 minutes; for details of hot water and service mode see box 5. The target room-temperature may not be reached.
box 22
box 25
C
[0a]
C C C C C
[0c] [0e] [0h] [0l] [0u]
Heat request, but no respons of the boiler
box 285
Recycling phase: The fan runs for 15 seconds at about 60% of maximum speed. "Extraction of residual fumes in boiler" The target room-temperature may not be reached. box 26
C
[0y]
C
[0y] ?1c]
The target room-temperature may not be reached.
box 27
Yes
2)
No heating operation and no hot water.
box 28
No
1)
box 27
C
[2f]
1) This error code may deactivate again automatically after a specific time (without reset). Heating and hot water are now available once more. 2) In the event of this malfunction, the pump is started up and remains in continuous operation in order to minimise the possibility of the heating system freezing up.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
18
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Symptoms
box 20 Display codes
Display indication
5
z
C C
Display code
Key to display code
Fault: The flow sensor has detected a temperature increase, in the heating system water, of over 5 °C/sec. Fault: The tacho signal from the fan has failed during the operating phase. Fault: The tacho signal from the fan is not present during the preoperative or operating phase. Fault: No current of air after a certain time. Fault: The fan runs too slowly or too fast. Fault: The flow sensor and safety sensor have detected a CH flow temperature of over 105 °C. Fault: The sensor test has failed. Fault: The contacts of the flow sensor and safety sensor are shorted to each other, or there is a short-circuit to earth (ground), or the flow or safety sensor has detected a CH flow temperature of above 130 °C. Fault: The contacts of the flow sensor or safety sensor are broken. Fault: During the ignition phase, the system has detected an insufficient ionisation current. Fault: After four startup attempts, the system has detected an insufficient ionisation current. Fault: The system has detected an ionisation current before burner startup. Fault: An ionisation current has been measured as soon as the burner shuts down. Fault: The flame goes out during the operating phase. Fault: The power supply was shut off during a crucial breakdown. Operating phase: Display test during startup phase: The code is displayed for a maximum of 1 second. Fault: The DBA control panel is defective. Fault: The contacts of the gas valve have been broken. Fault: The DBA control panel is defective. Fault: The contacts of the gas valve have been broken. Fault: The DBA control panel is defective.
Reset Other symptoms required?
No
1)
Diagnosis
box 27
[2p] [3a] ?3l] ?3l] ?3y] ?4a] ?4e] ?4l]
No
1)
box 29
Yes
2)
No heating operation and no hot water.
box 29
Yes
2)
No heating operation and no hot water. No heating operation and no hot water. No heating operation and no hot water.
box 30 box 31 box 32
Yes
2)
Yes
2)
Yes
2)
No heating operation and no hot water. No heating operation and no hot water.
box 33 box 34
Yes
2)
?4p] C [6a] ?6a] :6c] ?6c] C [6l] ?7c] !88| ?9a] ?9f] ?9h] ?9l] ?9l]
Yes
2)
No heating operation and no hot water.
box 35
No
1)
box 36
Yes
2)
No heating operation and no hot water.
box 36
Yes
2)
No heating operation and no hot water.
box 37
Yes
2)
No heating operation and no hot water.
box 38
No
1)
Yes
2)
No heating operation and no hot water.
box 39
Yes
2)
No heating operation and no hot water. No heating operation and no hot water. No heating operation and no hot water. No heating operation and no hot water. No heating operation and no hot water.
box 41 box 40 box 41 box 40 box 41
Yes
2)
Yes
2)
Yes
2)
Yes
2)
1) This error code may deactivate again automatically after a specific time (without reset). Heating and hot water are now available once more. 2) In the event of this malfunction, the pump is started up and remains in continuous operation in order to minimise the possibility of the heating system freezing up.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
19
5
box 20
Symptoms
Display codes
Display indication
z
Display code
Key to display code
Fault: The DBA control panel is defective. Fault: Short circuit in the gas valve. Fault: The contacts of the KIM (EEPROM on the DBA control panel circuit board) may be loose or short-circuited. Fault: The DBA control panel is defective.
Reset Other symptoms required?
Yes
2)
Diagnosis
box 41 box 41
?9p] ?9y] ?ef] ?e1] ?e4] ?ea] ?ec] C [re]
to
No heating operation and no hot water.
Yes No
1)
No heating operation and no hot water.
box 41
Yes
2)
No heating operation and no hot water.
box 41
Fault: Reset is carried out. This code appears after the reset button B is pressed for 5 seconds.
Applies only to a system-blocking error (flashing display code)
1) This error code may deactivate again automatically after a specific time (without reset). Heating and hot water are now available once more. 2) In the event of this malfunction, the pump is started up and remains in continuous operation in order to minimise the possibility of the heating system freezing up.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
20
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Diagnosis
6
6
box 21
Diagnosis No indication on DBA control panel display. Check to ensure that the power supply cable to the mains switch box has been installed correctly. Is the power supply cable to the mains switch box correctly installed? Yes: No:
[\/\/\|
step 1 step 2
step 3 step 4 step 5
Install the power supply cable correctly, see box 54. Check to ensure that the operating switch on the boiler DBA control panel is set to position "1" as per box 55. Is the operating switch on the boiler DBA control panel set to "I" (ON)? Yes: No:
step 4 step 3 box 42 step 7 step 6 box 42 step 10 step 9 box 42 step 22 step 21 box 42 box 41 step 15 box 42 step 17
step 6 step 7 step 8
Turn the operating switch on the DBA control panel of the boiler to position "1" (ON), see box 55. Check to the ensure that there is a 230V AC power supply at the mains switch. Is there a 230V AC supply at the mains switch? Yes: No:
step 9 step 10 step 11
Deal with any problem in the electrical system. Measure the resistance of the 230V AC power supply cable. Is the resistance of the 230V AC power supply cable within the specified limits? Yes: No:
step 12 step 13 step 14
Replace the cable loom (or the affected part thereof). Use a multimeter to check the fuse on the inside of the DBA control panel, see box 62 to 65. Is the fuse working correctly? Yes: No:
step 15 step 16
Replace fuse, see box 62. Is there any indication on the DBA control panel display? Yes: No:
step 17 step 18
Turn the operating switch on the DBA control panel of the boiler to position "0" (OFF), see box 43. Disconnect the following boiler components from the electrical power supply: pump, see box 92 fan, see box 71, item 1. Check the fuse again for correct functioning. Use a multimeter to check the fuse on the inside of the DBA control panel, see box 62. Is the fuse working correctly? Yes: No:
step 19 step 20
step 22 step 21
step 21 step 22 step 23
Replace fuse again, see box 62. Turn the operating switch on the DBA control panel of the boiler to position "1" (ON), see box 55. Is there any indication on the DBA control panel display? Yes: No:
step 27 step 24
step 24 step 25
Use a multimeter to check the power supply cables of the pump (box 95), the fan (box 69) and the glow ignitor (box 137) for signs of short circuiting. Are the cables in order? Yes: No:
step 27 step 26 box 42
step 26 step 27 step 28 step 29
Replace the cable harness (or the affected part thereof). Replace fuse again, see box 62. Turn the operating switch on the DBA control panel of the boiler to position "0" (OFF), see box 43. Connect the power supply plug of the pump in reverse. Turn the operating switch on the DBA control panel of the boiler to position "1" (ON), see box 55.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
21
6
box 21
step 30
Diagnosis
Is there any indication on the DBA control panel display?
Yes: No:
step 31 step 32 step 33 step 34 step 35 step 36
Replace the pump, see box 101. Replace fuse again, see box 62. Turn the operating switch on the DBA control panel of the boiler to position "0" (OFF), see box 43. Connect the power supply plug of the fan in reverse. Turn the operating switch on the DBA control panel of the boiler to position "1" (ON), see box 55. Is there any indication on the DBA control panel display? Yes: No:
step 33 step 31 step 32 step 33
step 37 step 38
Replace fan, see box 76. Replace fuse again, see box 62.
box 42 step 37 step 38 box 42
box 22
No (or insufficient) hot water, radiators, convectors, etc. may be heated without current heat requirement. step 1 step 2 step 3 step 4 Set the operating switch on the boiler DBA control panel to position "0" (OFF), see box 43, and set the other DBA control panel operating switch to position "1" (ON), see box 55. Open a hot water tap. Check that the hot water pipe directly beneath the (external) storage-type water heater warms up. Does the pipe warm up (to approx. 60 °C)? Yes: No: step 5 step 6 The cause of this fault does not lie with the boiler, but with the mains water supply. Check to see if the MCW inlet and DHW outlet have been incorrectly connected to the (external) storage-type water heater. Are the pipes connected correctly? Yes: No: step 7 step 8 step 9 Connect the pipeworks correctly. Close the shut-off valve in the MCW inlet and open a hot water tap at random to see if water is still flowing. Is this the case? Yes: No: step 10 step 11 step 12 The cause is a defective (thermostat-controlled) mixer tap, a thermostat-controlled mixer valve or a short circuit between the hot- and cold water circuits. Check to see if any other external part of the drinking-water system is a possible cause. Are such items detected? Yes: No: step 13 step 14 Place the affected components out of service. Check to ensure that the pre-adjusted setting corresponds to the hot water [60) box 14 supply. to ensure that the DHW temperature is adjusted to a high enough setting, see box 61. to see if the hot water supply has been shut off by the control system (ModuLink 250 RF). step 15 Are the adjustment settings in order? Yes: No: step 16 step 17 step 18 Adjust the settings. Check to see if the "hot water mode" indicator (H) or (I) lights up on the display, see box 11. Does the "hot water mode" indicator (H) or (I) light up? Yes: No: step 19 Check the turbine flow-meter, see box 104, or DWH temperature sensor of any external storage-type water heater that might be fitted.
step 5 step 39
step 8 step 7 box 42 step 10 step 11 box 42
step 13 box 42 box 42
step 17 step 16 box 42 step 25 step 19
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
22
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Diagnosis
box 22
step 20 Is the turbine flow-meter working correctly (along with DHW temperature sensor of any external storage-type water that might be fitted)? Replace the turbine flow-meter, or DHW temperature sensor of any external storage-type water heater that might be fitted. Check the cable of the turbine flow-meter, see box 112, or cable of the DHW temperature sensor of any external storage-type water heater that might be fitted. Is the cable correctly connected and free of damage? Yes: No: step 24 step 25 step 26 Replace the cable loom (or the affected part thereof). Check to ensure that the boiler starts up to supply hot water, see box 15. Does the boiler start up? Yes: No: step 27 step 28 step 29 Interpret current display codes box 20 and deal with fault. Check to ensure that the tap flow rate is correctly adjusted, see box 180. Is the tap flow rate correctly adjusted? Yes: No: step 30 step 31 Correctly adjust the tap flow rate, see box 180. Is an internal 3-way valve fitted? Yes: No: step 32 step 33 Check the movement of the servomotor of the Buderus 24V AC external 3-way valve, see box 211. Does the servomotor of the Buderus 24V AC external 3-way valve move correctly? Yes: No: step 34 step 35 Check the movement of the servomotor of the internal 3-way valve, see box 181.. Does the servomotor of the internal 3-way valve move correctly? Yes: No: step 36 step 37 Check to ensure that the the Buderus 24V AC external 3-way valve has been fitted correctly, see box 227. Has the Buderus 24V AC external 3-way valve been fitted correctly? Yes: No: step 38 step 39 step 40 Fit the Buderus 24V AC external 3-way valve in the correct way, see box 227. Check the drive mechanism of the internal 3-way valve, see box 195. Is the drive mechanism of the internal 3-way valve working correctly? Yes: No: step 41 step 42 step 43 Replace the drive mechanism of the internal 3-way valve, see box 198. Check the circulation for debris, see box 97. Is there any debris in the pump? Yes: No: step 44 step 45 Clean the pump, see box 97. The following components must be checked for soiling and/or damage: - combustion-air inlet pipework - heat exchanger - flue-gas pipework. Are the above-mentioned components clean and free of damage? Yes: No: step 47 Clean and/or replace the corresponding components. Yes: No:
6
step 21 step 22 step 23
step 22 step 21 box 42
box 41 step 24 box 42 step 28 step 27 box 42 step 31 step 30 step 34 step 32 step 36 step 63 step 39 step 57
step 69 step 38 box 42 step 42 step 41 box 42 step 44 step 45 box 42
step 46
step 48 step 47 box 42
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
23
6
box 22
step 48 step 49
Diagnosis
Check the standing and working gas pressures, see box 230. Are the standing and working pressures correct? Yes: No:
step 50 step 51 step 52
If the standing and working gas input pressures are not detected, consult your gas utility company. Check the gas/air ratio, see box 233. Is the gas/air ratio correct? Yes: No:
step 51 step 50 box 42 step 54 step 53 box 42 step 56 box 41 box 42 step 59 step 60 box 42 box 41 step 62 box 42
step 53 step 54 step 55
Adjust the gas/air ratio, see box 233. Check the plate heat exchanger or the external hot water cylinder for furring. Is the plate heat exchanger or hot water cylinder furred up? Yes: No:
step 56 step 57 step 58
Decalcify the plate heat exchanger and/or hot water cylinder, see from box 269. 3-way valve: Check the startup of the servomotor of the internal 3-way valve, see box 181 and box 185. Does the servomotor of the internal 3-way valve start up correctly? Yes: No:
step 59 step 60 step 61
Replace the servomotor of the internal 3-way valve, see box 190. Check the wiring of the internal 3-way valve, see box 191. Is the cable correctly connected and free of damage? Yes: No:
step 62 step 63 step 64
Replace the cable loom (or the affected part thereof). Check to ensure that the Buderus 24V AC external 3-way valve has actuated correctly, see box 212 and box 228 parts 1 and 2. Does the Buderus 24V AC external 3-way valve actuate correctly? Yes: No:
step 65 step 66 step 67
Replace the servomotor of the Buderus 24V AC external 3-way valve, see box 217. Check the wiring of the Buderus 24V AC external 3-way valve, see box 220. Is the wiring of the Buderus 24V AC external 3-way valve in correct condition? Yes: No:
step 65 step 66 box 42 step 71 step 68 box 42 step 42 step 71
step 68 step 69 step 70
Replace the wiring of the Buderus 24V AC external 3-way valve. Check the drive mechanism of the Buderus 24V AC external 3-way valve, see box 221. Is the drive mechanism of the Buderus 24V AC external 3-way valve working correctly? Yes: No:
step 71 step 72 step 73
Replace the drive mechanism of the Buderus 24V AC external 3-way valve, see box 221. Check the wiring of the Buderus 24V AC external 3-way valve between the connection box or moving plugand-socket connection and the motor of the Buderus 24V AC external 3-way valve, see box 287. Is the wiring in order? Yes: No:
step 74
Replace the cable loom (or the affected part thereof).
box 41 step 74 box 42
box 23
On combi boilers: hot water available, but no heating operation. On system boilers: no heating operation. Hot water may be available, but no heating operation. step 1 Check to ensure that the power supply cable to the mains switch box has been installed correctly, see box 54.
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
24
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
Diagnosis
box 23
step 2 step 3 Check to ensure that the preset room temperature or heating configuration of the Buderus controls or ON/ OFF controller has been adjusted to a high enough setting (see operating instructions). Is the preset room temperature or heating configuration of the Buderus controls or ON/OFF controller adjusted to a high enough setting? Adjust the preset room temperature controller or heating configuration of the Buderus controls or ON/OFF controller to a higher setting (see operating instructions). Check to see if the "heating requirement" (K) indicator lights up on the display, see box 11. Does the "heating requirement" (K) indicator light up? Yes: No: step 7 step 8 Check the Buderus controls or ON/OFF controller as per box 177. Is the Buderus controls or ON/OFF controller working correctly? Yes: No: step 9 step 10 step 11 step 12 Replace the thermostat cable. Replace the Buderus controls or ON/OFF controller. Check to ensure that the CH flow temperature at the DBA control panel or on the Buderus controls or ON/ OFF controller is adjusted to a high enough setting as per box 14 and box 61 . Is the CH flow temperature adjusted to a high enough setting? Yes: No: step 13 Are enough thermostatic valves open on the radiators, convectors, etc? Yes: No: step 14 step 15 step 16 step 17 Open more thermostatic valves on the radiators, convectors, etc. Adjust the CH flow temperature as per box 14 and box 61. Ensure that the Buderus controls or ON/OFF controller are calling for a heating demand. Check to ensure that the CH flow temperature is correctly adjusted, see box 14. Is the CH flow temperature adjusted to a high enough setting? Yes: No: step 18 step 19 Adjust the CH flow temperature to a higher setting, see box 14. Is the CH flow temperature of the boiler sufficient to heat the building? Yes: No: step 20 step 21 Install a larger boiler. Is there a hot water supply? Yes: No: step 22 Is an internal 3-way valve fitted? Yes: No: step 23 step 24 Check the movement of the servomotor of the internal 3-way valve, see box 181. Does the servomotor of the internal 3-way valve move correctly? Yes: No: step 25 step 26 Check the drive mechanism of the internal 3-way valve, see box 195. Is the drive mechanism working correctly? Yes: No: step 27 step 28 step 29 Replace the drive mechanism of the internal 3-way valve, see box 198. Check the actuation of the servomotor of the internal 3-way valve, see box 185. Does the servomotor of the internal 3-way valve start up correctly? Yes: No: Yes: No:
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step 4 step 5 step 6
step 5 step 4 box 42
step 11 step 7 step 9 step 10 box 42 box 42
step 13 step 15 step 16 step 14 box 42 box 42
step 19 step 18 box 42 step 21 step 20 box 42 step 22 box 41 step 23 step 34 step 25 step 28 box 42 step 27 box 42 step 30 step 31
We reserve the right to make technical modifications
Buderus Ltd. · http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C · Issued 02/2006
25
6
box 23
step 30 step 31 step 32
Diagnosis
Replace the servomotor of the internal 3-way valve, see box 190. Check the power supply cable of the internal 3-way valve, see box 191. Is the power supply cable of the internal 3-way valve in good condition? Yes: No:
box 42 box 41 step 33 box 42 step 36 step 39
step 33 step 34 step 35
Replace the cable loom (or the affected part thereof). Check the movement of the servomotor of the Buderus 24V AC external 3-way valve, see box 211. Does the servomotor of the Buderus 24V AC external 3-way valve operate correctly? Yes: No:
step 36 step 37
Check to ensure that the the Buderus 24V AC external 3-way valve has been fitted correctly, see box 227. Has the Buderus 24V AC external 3-way valve been fitted correctly? Yes: No:
step 38 step 39 step 40
Install the Buderus 24V AC external 3-way valve correctly, see box 227. Check to ensure that the Buderus 24V AC external 3-way valve is actuated correctly, see box 212 and box 228. Does the Buderus 24V AC external 3-way valve actuate correctly? Yes: No:
step 45 step 38 box 42
step 41 step 42 step 43
Replace the servomotor of the Buderus 24V AC external 3-way valve, see box 217. Check the wiring of the Buderus 24V AC external 3-way valve, see box 220. Is the wiring of the Buderus 24V AC external 3-way valve in correct condition? Yes: No:
step 41 step 42 box 42 step 47 step 44 box 42 box 41 step 47 box 42
step 44 step 45 step 46
Replace the wiring of the Buderus 24V AC external 3-way valve. Check the drive mechanism of the Buderus 24V AC external 3-way valve, see box 221. Is the drive mechanism of the Buderus 24V AC external 3-way valve working correctly? Yes: No:
step 47 step 48
Replace the internal components of the Buderus 24V AC external 3-way valve, see box 224. Check the wiring of the Buderus 24V AC external 3-way valve between the connection box or moving plugand-socket connection and the DBA control panel as per box 287.
box 24
On combi boiler supply: hot water available, but no heating operation. On system boiler supply: no heating operation. Hot water may be available, but no heating operation. step 1 step 2 Check to ensure that the power supply cable to the RTH converter/Junction box has been installed correctly, see box 285. Is the 230V connection to the RTH converter/Junction box fitted correctly? Yes: No: step 3 step 4 Correctly attach the switch live to terminal 1 and Neutral to terminal 2 on the 230V connector, see box 285. Disconnect black leads from terminals 1 & 2 on the back of the DBA and test for continuity between the two leads. No continuity check S/L and N connections are made correctly and that there is 230v between the two. Replace RTH converter/Junction box. Continuity reconnect the cables to terminals 1 & 2 and check the connections between the terminals and the DBA. Is the volt free connection to the RTH converter/Junction box fitted correctly? Yes: No: step 6 Check to ensure that the connections of the external control unit are attached to terminal 1 and 2 of the connection block, indicated by a clock inside a rectangle, see box 286 and box 285 (item 3).
box 42
step 4 step 3
step 5
step 6 step 8
We reserve the right to make technical modifications
Buderus Ltd. · http://ww