Worcester 24Si II series Manuals

24SiII / 28SiII WALL MOUNTED COMBINATION BOILERS FOR CENTRAL HEATING AND MAINS FED DOMESTIC HOT WATER INSTALLATION AND SERVICING INSTRUCTIONS This appliance is for use with Natural Gas or LPG (Cat II 2H3P TYPE C12 & C32) 24SiII GC NUMBER 47 311 65 (N.G.) GC NUMBER 47 311 66 (L.P.G.) 28SiII GC NUMBER 47 311 67 (N.G.) GC NUMBER 47 311 68 (L.P.G.) GB/IE APPLIANCE OUTPUTS Domestic Central Heating Hot Water 24Si II 28Si II 24Si II 28Si II Minimum 6.9 kW 8.1 kW 6.9 kW 8.1 kW Maximum 24 kW 28 kW 24 kW 28 kW IMPORTANT: THESE INSTRUCTIONS APPLY IN THE GB/IE ONLY AND MUST BE LEFT WITH THE USER OR AT THE GAS METER It is IMPORTANT to read the instructions before starting work - they have been written to make the installation easier and prevent hold-ups. 1.1 Gas Safety (Installation & Use) Regulations 1998: The appliance is suitable for installation in GB/IE only and should be installed in accordance with the rules in force. It is the law in GB that a competent person in accordance with the above regulations installs all gas appliances. Failure to install appliances correctly could lead to prosecution. It is in your interest, and that of safety, to ensure compliance with the law. 1.2 The manufacturers notes must not be taken, in any way, as overriding statutory obligations. 1.3 The compliance with a British Standard or European Norm does not, in itself, confer immunity from legal obligations. 1.4.1 The installation of the appliance must be in accordance with the relevant requirements of the Gas Safety Regulations, current IEE Regulations, Building Regulations, Building Standards (Scotland) and local water by-laws. 1.4.2 In Eire the installation must be carried out by a competent person and installed in accordance with IS 813, Domestic Gas Installations (Edition 2), the current building regulations and the electrical installation must follow the ETCI rules. 1.5 The installation should follow the recommendations of the following British Standards unless otherwise indicated. BS5440:1 - Flues and ventilation for gas appliances: Flues BS5440:2 - Flues and ventilation for gas appliances: Air supply. BS5449 - Central heating for domestic premises. BS5482 - Domestic propane gas burning installations. BS5546:1 - Installation of gas hot water supplies. BS6700 - Domestic water supply in buildings. BS6798 - Installation of gas fired hot water boilers. BS6891- Low pressure gas pipework installations upto 28mm (R1). BS7593 - Water treatment. BS7671 - Requirements for electrical installations. 1.6 The appliance does not contain any substances which are harmful to health. 1.7 In certain circumstances, the installer can be held responsible, not only for mistakes on his part but also for damage resulting from the use of faulty materials. We advise that, to avoid any risk, only quality approved branded fittings are used. 1.8 LPG Installation: The appliance shall not be installed in a room or internal space below ground level when it is intended for use with LPG. This does not preclude the installation into rooms, which are basements with respect to one side of the building but open to the ground on the opposite side. 1.9 These instructions cover, as far as possible, the foreseeable situations, which may arise. Contact Worcester Heat Systems Technical Department, Telephone: 08705 266241, for advice on specific installations. 2.1 The initiative is the new code of practice to encourage the correct installation, commissioning and servicing of domestic central heating boilers and system equipment. The 'Log-book' is a vital document that must be completed by the installer at the time of installation. It confirms that the boiler has been installed and commissioned according to the manufacturers instructions. A declaration of conformity (Refer to IS 813 Annex D1) must be completed by the installer and a copy supplied to the appliance operator for boilers installed in Eire. Without the completion of the Log-book and/or declaration, manufacturers may refuse to respond to a call-out from a householder, who will be advised that he or she must call back the installer, who has not fulfilled his obligations to record the information required by the initiative. Service: To ensure continued efficient operation of the appliance it must be checked at regular intervals. The frequency of servicing will depend upon the particular installation conditions and usage, but once per year should generally be adequate. The extent of the service required by the appliance is determined by the operating condition of the appliance when tested by fully qualified engineers. Any service work must be carried out by competent registered engineers (CORGI in GB). 2.2 General Information The appliance is set to give the maximum output of 28 kW [28Si II] or 24kW [24Si II] to the domestic hot water and to the heating system. The hot water flow rate is limited to a nominal 10 l/min [28Si II] or 8 l/min [24Si II] at a maximum temperature rise of 40°C. The sanitary water section of the appliance is suitable for mains water pressure of upto 10bar. Kits are available to convert the appliance from Natural Gas to Propane operation and vice versa. 2.3 Electrical Supply 230V - 50Hz. Load 180 watts. External fuse 3A (to BS1362), Internal fuses F1 - 2A, F2 - 1.25A (20mm). 2.4 Gas Supply The appliances require a maximum of 3.25 m3/h of natural gas (G20) or 1.25 m3/h of propane (G31) [28Si II] or 2.8 m3/h of natural gas (G20) or 1.08 m3/h of propane (G31) [24Si II]. The installation and the connection of the gas supply to the appliance must be in accordance with BS6891. The meter or regulator should deliver a dynamic pressure of 20 mbar (G20) or 37mbar (G31) at the appliance, which is equivalent to about 19 mbar or 36 mbar at the gas valve inlet pressure test point. 2.5 Installation The appliance is suitable for indoor installation only and for use with a sealed system only. Do not place anything on top of the appliance. This is a room sealed appliance and a separate combustion air supply is not required in any room or compartment in which the appliance is fitted. If the appliance is fitted in a cupboard or a compartment is built around it after installation, then the structure must conform to the requirements of BS6798 and BS5440 Part 2. However, because of the low casing losses, there is no need for cooling ventilation openings in 2. Introduction 1. Installation Regulations 2 1. Installation Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2 10. Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 9 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2 11. Installing the Appliance . . . . . . . . . . . . . . . . . . . . . . . . . . Page 12 3. Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4 12. Commissioning the Appliance . . . . . . . . . . . . . . . . . . . . Page 19 4. Siting the Appliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 7 13. Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 21 5. Flue Terminal Positions. . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 7 14. Inspection and Service. . . . . . . . . . . . . . . . . . . . . . . . . . . Page 21 6. Air Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 8 15. Replacement of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 24 7. Sealed System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 8 16. Short Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 30 Open Vent System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 8 17. Operational Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . Page 32 8. Domestic Hot Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 9 18. Fault Finding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 34 9. Gas Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 9 19. Conversion Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . Page 42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contents the compartment provided the increased clearances are used. See Fig. 5. The spaces specified for servicing must be maintained.(See Table 8). There is space for the service pipes to pass at the back of the appliance. 2.6 Flue Multi-Directional Horizontal Flue Kit. Standard Flue Kit can be adjusted from 425mm to 725mm without cutting. The minimum length is 265 mm with cutting. Extended flue lengths are available upto a maximum of 4m for natural gas appliances and 2.5m for LPG. Optional 45° and 90° flue bend kits are available NOTE: When using flue bends the maximum flue length is reduced (see Section 11.12). If access to the flue terminal will be a problem then a kit is available to enable the horizontal flue to be fitted from inside the house. Do not allow the flue terminal to the outside wall to become obstructed or damaged. A Tower guard type K2 CG 393553 is available from Tower Flue Components, Vale Rise, Tonbridge TN9 1TB. A vertical flue system is available. 2.7 Controls The appliance has controls for switching the appliance On or Off, [this does not electrically isolate the appliance] for adjusting the CH and DHW temperatures. The CH control knob also switches the CH off and on. A programmable 'wire free' room thermostat or a facia mounted programmer or clock is available. A room thermostat and/or an externally mounted programmer for mains voltage operation may be connected to the appliance. 2.8 System All dirt must be flushed from the system before connecting the appliance. The system can be pre-piped and flushed before the appliance is fitted. The connections in the system must withstand an operating pressure of upto 3 bar. Radiator valves must conform to BS2767: 10:1977. Table 3 gives the pump head available for the system and the required temperature differential. A drain cock must be fitted to the lowest point and an air vent to the highest point of the system. 2.9 Showers, Bidets, Taps and Mixing Valves All taps and mixing valves must be suitable for the available mains pressure and temperatures upto 65oC. It may be necessary to fit a pressure reducing valve. Hot and cold mains fed water can be supplied to overrim bidets but is subject to local water company requirements. The flow of water from individual outlets varies on all mains fed systems that are not fitted with flow balancing valves. Thermostatically controlled or pressure equalising shower valves give extra comfort and protection. If a pressure equalising valve is fitted then the domestic hot water temperature should be set to maximum. 2.10 Safety The appliance must not be operated with the inner casing cover removed or without being full of water and pressurised. The gas and electricity supplies must be turned off before working on the appliance. Temperature monitoring controls are fitted to prevent overheating. Automatic frost protection is provided together with automatic pump seizure protection. The gas valve solenoids are automatically checked for gas soundness. IMPORTANT: Where back-flow prevention devices, including water meters, are fitted the expansion of hot water into cold water main can be prevented. This can result in a pressure build-up that may cause damage to the boiler and household devices such as showers, washing machines etc. In these cases we recommend that a mini-expansion vessel be fitted adjacent to the boiler in the cold water supply pipe. 2.11.1 Operation Central Heating: A demand for heat will ignite the burner. It will operate at minimum pressure for 15 seconds before increasing to the maximum pressure over a period of 1 minute and then automatically match the system requirements. At the end of the demand the burner will go out, the pump will continue to run for upto 4 minutes or the fan for 15 seconds. There is an anti-cycle time of 3 minutes. 2.11.2 Domestic Hot Water: A demand for hot water will light the burner. The pressure will immediately rise to maximum. At the end of the demand the fan will continue to run for 15 seconds if there is no heating demand. There is an anti-cycle time of 10 seconds. 2.11.3 Domestic Hot Water and Central Heating Mode. The demand for hot water will override the CH function when the appliance is in the heating and hot water mode of operation. In winter it may be necessary to reduce the flow at the taps to maintain the delivery temperature. Fig. 1. Facia controls 3 Fig. 2. Water flow diagram. 1 2 3 4 7 6 1. Mains On/Off control 5. Optional programmer 2. CH temperature control 6. Lockout indicator light and 3. DHW temperature control reset button 4. System pressure gauge 7. Burner indicator light 5 1 2 3 4 7 6 1. CH flow 7. Circulating pump 2. Domestic hot water flow 8. Expansion vessel 3. Domestic hot water supply 9. Primary heat exchanger 4. CH return 10. Automatic air vent 5. Pressure relife valve discharge 11. By pass 6. Domestic water flow turbine 5 8 9 10 11 4 3. Technical Data MAXIMUM AVAILABLE PUMP HEAD BOILER OUTPUT HEAD MIN. FLOW RATE kW Metres L/min. °C 6.9 5.2 9 11 24 1.8 22 15.5 28 1.8 22 18 Table 3 MECHANICAL SPECIFICATIONS 24Si II 28Si II CENTRAL HEATING FLOW - COMPRESSION 22mm 22mm RETURN - COMPRESSION 22mm 22mm COLD WATER INLET - COMPRESSION 15mm 15mm DOMESTIC WATER FLOW - COMPRESSION 15mm 15mm GAS INLET Rp 3⁄4 Rp 3⁄4 RELIEF VALVE DISCHARGE (PUSH-IN) 15mm 15mm CASING HEIGHT 740mm 740mm CASING WIDTH 400mm 440mm CASING DEPTH 360mm 360mm WEIGHT - LIFT 36kg 36kg WEIGHT - PACKAGED 48kg 50kg WEIGHT - DRY 39kg 40kg Table 4 FLUE DETAILS HORIZONTAL FLUE G20 LPG WALL HOLE DIAMETER EXTERNAL FIX mm 110 110 INTERNAL FIX mm 130 130 STANDARD FLUE MINIMUM LENGTH mm 275/*425 275/*425 MAXIMUM LENGTH mm 725 725 EXTENDED FLUE MAXIMUM LENGTH mm 4000 2500 FLUE ASSEMBLY DIAMETER mm 100 100 Table 2. FLOW/RETURN DIFFERENTIAL * NOTE : Minimum uncut length NOMINAL BOILER RATINGS (10 Minutes After Lighting) BOILER ADJUSTED FOR G20 (Natural Gas) OUTPUT INPUT (Net) GAS RATE kW kW m bar. m3/h 8.1 9.2 0.7 0.97 28 30.7 13.1 3.25 BOILER ADJUSTED FOR G31 (Propane) 8.1 9.2 2.8 0.38 28 30.7 34.5 1.25 Table 1. 28Si II BURNER PRESSURE NOMINAL BOILER RATINGS (10 Minutes After Lighting) BOILER ADJUSTED FOR G20 (Natural Gas) OUTPUT INPUT (Net) GAS RATE kW kW m bar. m3/h 6.9 7.9 0.9 0.84 24 26.4 12.1 2.8 BOILER ADJUSTED FOR G31 (Propane) 6.9 7.9 3.1 0.32 24 26.4 35.0 1.08 Table 1. 24Si II BURNER PRESSURE Natural Gas: Net Input = Gross Input x 0.901 LPG (Propane): Net Input = Gross Input x 0.922 NOTE: With longer flue lengths, not using a restrictor, the minimum burner pressure will rise, naturally due to the flue, to 1.1mbar on G20 appliances only.