Part No. DOC 10 Rev.
LIST OF CONTENTS Section 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Subject Page User instructions ...................................... Technical information .............................. General boiler information ....................... Boiler installation ..................................... Fill and vent the system ........................... Commissioning ......................................... Information for the user ........................... Boiler servicing ........................................
1 - USER INSTRUCTIONS 1.1 1.3 About your boiler Your Combi 70 or Combi 90 boiler is fully automatic when the Boiler On/Off switch is set to ON, and will provide domestic hot water at mains pressure on demand and central heating when the boiler and heating system controls call for it. A green 'Boiler On' neon on the front of the boiler lights when the boiler is switched on, but does not necessarily indicate that the burner is firing.
1 - USER INSTRUCTIONS 1.4 Lighting your boiler (see Fig. A) 1.7 1 Ensure that - There is sufficient fuel in the supply tank and all fuel supply valves are open, the water supply is on, the electricity supply to the boiler is off, the Boiler On/Off switch is set to OFF, the Heating switch is set to TIMED, the black pointer on the pressure gauge is not below the red pointer, the room thermostat (if fitted) is at the desired setting and the timer is correctly set.
1 - USER INSTRUCTIONS 1.9 Useful tips To ensure that the hot water performance is not reduced first thing in the morning, or in the evening if the heating is off through the day, set the heating timer to switch the heating on at least 30 minutes before hot water will normally be required in the morning (or evening). When setting the times for the 'on' periods it is useful to remember that it might take up to an hour for the house to become warm, especially in colder weather.
2 - BOILER TECHNICAL INFORMATION 2.1 Boiler technical data Model Boiler water content * Weight (dry) Max. heat input (Kerosene) Combi 70 Combi 90 litre 80 40 gal 17.6 8.8 kg 158 158 lb 348 348 kW 22.0 27.
2 - BOILER TECHNICAL INFORMATION 2.2 Combi 70 & 90 oil boilers using class C2 Kerosene Note: All boilers are despatched for use with Kerosene. Heat Output Net Heat Input Net eff. ** Head Nozzle (kW) (Btu/h) (kW) (Btu/h) (%) type size 20.5 70 000 22.5 76 900 93.0 26.4 90 000 27.6 94 200 95.8 2.3 Oil press. Smoke Fuel flow Net flue gas Flue gas mass CO2 rate (kg/h) temp. (°C) flow rate (kg/h) (%) (bar) No. LD2SX short 0.60/60°EH 8.5 0-1 1.87 211 34.8 11.5 0.75/60°EH 9.5 0-1 2.
2 - BOILER TECHNICAL INFORMATION 2.5 Boiler dimensions Fig. 1 Note: Water connections may be from the left or right hand side. If using side exit flue, it must be on the opposite side to the top water connections. 2.6 Water schematic of boiler Fig.
3 - GENERAL BOILER INFORMATION 3.1 Boiler description 3.2 The Combi 70 and Combi 90 automatic pressure jet oil boilers have been designed for use with a sealed central heating system and will provide domestic hot water at mains pressure. The boiler is supplied with the burner fitted and suitable for a conventional flue. If the boiler is to be used with a balanced flue, a Balanced Flue Kit is required.
3 - GENERAL BOILER INFORMATION 3.3 Delivery Conventional flue models are supplied in one pack, containing the cased boiler with the burner and control panel fitted, and literature pack. Balanced flue models are supplied in two packs, containing the following:Carton 1 The cased boiler with burner and control panel fitted, and literature pack. Carton 2 The balanced flue kit - low, high level or vertical, as ordered. A terminal guard is supplied with a low level flue kit.
3 - GENERAL BOILER INFORMATION Fig. 3 - Single pipe system Fig. 4 - Two pipe system 2 Avoid the bottom of the tank being more than 3 m below the burner. 3 A non-return valve should be fitted in the supply pipe together with the filter and fire valve. A non-return valve should be fitted in the return pipe if the top of the tank is above the burner.
3 - GENERAL BOILER INFORMATION Fig. 5 - Tiger loop system Tiger Loop 1/4" BSP female connections RETURN FROM PUMP SUPPLY TO PUMP SUPPLY FROM TANK Fig. 6 - Tiger loop 3.4.5 Tiger Loop system - (See Figs. 5 and 6) 3.4.6 Two pipe oil supplies 1 When the storage tank is below the burner, an alternative to a two pipe system can be achieved using the Tiger Loop oil deaerator. This effectively removes the air from the oil supply on a single pipe lift. See Fig.
3 - GENERAL BOILER INFORMATION 8 In the event of an electrical fault after installation of the boiler, the following electrical system checks must be carried out:- Short circuit, Polarity, Earth continuity and Resistance to earth. 7 6 3.6 Air supply 5 See Figs. 8 and 9 4 8 3 1 2 Fig.
3 - GENERAL BOILER INFORMATION Fig. 8 - Air supply for room sealed balanced flue boilers Fig. 9 - Combustion and ventilation air supply for conventional flue boilers Minimum size of air vents required - see Figs.
3 - GENERAL BOILER INFORMATION 3.7 Conventional flue system See Fig. 10 Grant boilers have high operating efficiencies. Care must be taken to ensure the flue system is suitable for the low flue gas temperatures. 1 An insulated flue terminating in a down draught free area, i.e. at least 1 m above the point of exit through the roof or preferably above the ridge level, will normally provide the necessary draught of at least 8.7 N/m2 (0.035 in wg) as measured close to the boiler connection.
3 - GENERAL BOILER INFORMATION 3.8 Connect a conventional flue 1 Remove the insulation from the rear top panel (do not discard it) and remove the blanking panel. Discard the panel, but retain the nuts and washers. 2 Unscrew the protective covers from the studs on the flue dress panel, supplied in the literature pack. Place the panel in position in the rear case top panel and secure in place using the washers and nuts previously removed.
3 - GENERAL BOILER INFORMATION Fig. 11 - Clearances for Balanced flues A B C D E F G H I J K L M Terminal position Below a gutter or sanitary pipework Horizontal from an opening, air brick or window Above ground or balcony level Below eaves or balcony From an internal or external corner From a terminal facing the terminal From a surface facing the terminal Vertical from terminals on the same wall Horizontal from terminals on the same wall Below an opening, air brick, window etc.
3 - GENERAL BOILER INFORMATION 3.10 Frost protection 3.12 Water connections For additional protection of either the entire heating system, or the boiler and localised pipework, it is recommended that a frost thermostat be installed. Refer to section 10 for connection details. To protect the heating system the frost thermostat should be sited within the house in such a place that it can detect any rise and fall in the ambient air temperature, i.e. in a room with a radiator.
3 - GENERAL BOILER INFORMATION d Automatic air vent, fitted to the top of the boiler, ensures the boiler is vented. e Filling loop. This must be isolated and disconnected after filling the system. 3 Using the expansion vessel as supplied and an initial system pressure (cold) of 0.8 bar, a heating system volume of approximately 77 or 117 litres can be used for the Combi 70 and 90 respectively. For further guidance refer to BS 7074:1. Refer to section 5.1 for further details of the expansion vessel.
3 - GENERAL BOILER INFORMATION 3.14 Domestic hot water system 1 A hot water flow rate of up to 24 litres/min is available, dependant on mains water pressure. To maintain a longer and more consistent hot water temperature, a flow restrictor is factory fitted to limit the flow rate to approximately 15 litres/min. The flow restrictor is located in the outlet side of the cold water inlet isolating valve. 2 The incoming mains water pressure should be between 1 and 8 bar to ensure efficient operation.
3 - GENERAL BOILER INFORMATION 3.16 Method of operation Once the boiler is switched on (amber neon on) it will always provide domestic hot water upon demand. The timer only controls the operating times of the central heating. When central heating is not required, the timer switch should be set to OFF. Domestic hot water supply always takes priority over central heating.
4 - BOILER INSTALLATION Fig. 13 - Square low level balanced flue Fig. 13a - Concentric low level balanced flue Dimension (mm) Combi 70 Combi 90 A (dia) 175 175 B (min) 1200 1195 B (max) 2100 2095 C (side) 112 110 Fig.
4 - BOILER INSTALLATION Fig. 15 - High level balanced flue 4.3 High level and vertical balanced flue Fitting instructions for the high level balanced flue and vertical balanced flue are supplied with the flue kits. Adjustable sections: The adjustable extensions are telescopic. The wall terminal section is adjustable and is suitable for a wall thickness of 215 mm to 450 mm. Simply adjust to the required length using a twisting motion. The outer pipes must overlap by a minimum of 25 mm.
4 - BOILER INSTALLATION 4.4 Make the water connections Note: Water connections may be from the left or right hand side. If using low level side exit flue, the flue must be on the opposite side to the top water connections. See Fig. 19 or 20 for flue/water connection arrangements. 1 Fit any elbows, bushes etc. to the heating return connection (bottom) before placing the boiler in position if access will be restricted. Do not forget to plug the unused connection.
4 - BOILER INSTALLATION Fig. 17 - Combi 70 Left hand low level flue - Right hand water connections Right hand low level flue - Left hand water connections Rear low level flue - Right hand water connections Fig.
4 - BOILER INSTALLATION Fig.
4 - BOILER INSTALLATION Fig. 19 - Combi 90 Left hand low level flue - Right hand water connections Right hand low level flue - Left hand water connections Rear low level flue - Right hand water connections Fig.
4 - BOILER INSTALLATION Fig.
4 - BOILER INSTALLATION 4.5 Fit a low level balanced flue (square only) To fit a concentric (round) low level, high level or vertical balanced flue, refer to the instructions supplied with the kit. 1 Lift off the boiler case top panels. Remove and discard the appropriate blanking panel from the rear or side of the boiler casing as required. 2 Unpack the flue kit. 3 Place the circular fibre gasket into the boiler flue spigot. See Fig. 21. Fig.
4 - BOILER INSTALLATION Important notes: a When engaging the flue assembly over the flue elbow, take care not to dislodge the seal from the recess in the flue pipe. b The flue pipe and seal are pre lubricated. Soap solutions must not be used. c The elbow must be inserted to a minimum depth of 60 mm past the flue seal. d For Boiler House models the wall sleeve should overhang the casing by 20 mm.
4 - BOILER INSTALLATION Fig. 29 Fig. 30 13 Remove and discard the conventional flue flexible air tube supplied with the boiler from the burner air spigot retaining the clamp. Extend the flexible air tube supplied with the flue kit over the top of the boiler water jacket, passing the tube under the control panel and across the front of the boiler. Locate the end of the tube over the burner air supply spigot and secure using the clamp previously removed.
4 - BOILER INSTALLATION 4.6 Connect the power supply 4.8 1 Remove the two screws securing the boiler terminal block cover (see Fig. 17 or 19) and lift off the cover. Remove the two screws securing the cable clamp and open the clamp.
4 - BOILER INSTALLATION 4.9 7 Remove the two screws securing the terminal block cover (see Fig. 17 or 19) and lift off the cover. Remove the link from terminals 13 and 14. Optional plug-in 7 day electronic timer Important: Ensure electrical supply to boiler has been isolated before fitting the timer. 8 Fit the 6-way plug on the timer wiring harness, firmly into the 6-way socket, to connect the timer to the boiler. 1 The Electronic Timer Kit (Ref.
5 - FILL AND VENT THE SYSTEM 5.1 Expansion vessel pressure The expansion vessel fitted is supplied with a charge pressure of 1.0 bar (equivalent to a max. static head of 10.2 metres). The charge pressure must not be less than the actual static head at the point of connection (see Fig. 12). Do not pressurise the vessel above 1.5 bar. The air pressure in the vessel must be checked annually.
6 - COMMISSIONING Refer to Fig. 32 for boiler controls Fig. 32 - shown with pipework cover removed It is important that the following commissioning procedure is carried out to ensure safe and efficient operation of the boiler. Note: Check that the baffles are in position and that the cleaning cover is correctly fitted and a good seal made. 1 Remove the pipework cover and check that the water system has been vented and pressurised, and there are no leaks. 2 Check that all fuel line valves are open.
6 - COMMISSIONING 11 a Having ensured that there are no oil leaks, replace the burner cover. Tighten the two fixing screws. Ensure the flexible air tube is connected to the burner. b Replace the plinth (if it was removed). Locate the left hand side over the locating stud and locate the slot in the right hand side over the screw previously loosened. Tighten the fixing screw. 12 Relight the boiler and allow it to run for 20 minutes then check the following:CO2 level, Flue gas temperature and Smoke Number.
7 - INFORMATION FOR THE USER The User must be advised (and demonstrated if necessary) of the following important points:- 7 Tell the user the system pressure and show them the position of the safety valve discharge pipe. 1 How to light and turn off the boiler and how to operate the system controls. 8 Show the User how to reset the overheat thermostat and how to restart the boiler if it goes to 'Lock-out'.
8 - BOILER SERVICING 8.2 Dismantling prior to servicing 1 Open the case door and remove the grey plinth loosen the screw securing the right hand side of the plinth inside the case. Withdraw the plinth forward from the right and away from the case. Cleaning cover 2 Carefully lift up the expansion vessel and remove it from the front of the boiler. Place it on the floor, taking care not to strain the flexible pipe. Baffle No. 4 Baffle No. 3 3 Disconnect the flexible air tube from the burner.
8 - BOILER SERVICING Fig. 34 - Combi 90 baffle positions 8.4 Cleaning the burner See section 12.1 1 Combustion head - Loosen the two screws securing the combustion head to the burner flange and withdraw the head. Clean and replace the combustion head. electrodes away from the nozzle. Remove the nozzle using a good fitting spanner (16 mm). The use of an ill-fitting spanner will damage the nozzle and could lead to an incorrect flame pattern.
8 - BOILER SERVICING 4 Photocell - The photocell is a push-fit in the burner body, see Fig. 36. Carefully pull out the photocell to clean. 5 Fan - With the air intake spigot removed, remove the screws securing the fan housing cover (R/H side of burner) and remove the cover. Inspect the fan and housing and clean as necessary. Replace the cover. 1 3 Photocell 6 Pump filter - With the burner cover removed, remove the four screws securing the pump end cover. Remove the filter and wash in Kerosene.
9 - REPLACEMENT OF BOILER COMPONENTS Fig. 37 - Boiler components (plinth and pipework cover removed for clarity) 8 Fit a replacement pump using the reverse of the above procedure, ensuring the sealing washers are correctly fitted in the pump unions, and that pump flow direction (as indicated by arrow on pump body) is correct. Set the pump speed selector switch to maximum. 9 Open the pump isolating valve and the primary return valve, then refill the central heating system as described in section 5.
9 - REPLACEMENT OF BOILER COMPONENTS 9.3 Diverter valve diaphragm 1 Follow steps 1 to 4 of section 9.2. 2 Unscrew and disconnect pipe unions 1, 5 & 9. See Fig. 38 or 39. Remove the vertical 15 mm pipe from the boiler. 3 Unscrew and remove all eight screws from the diaphragm housing. Unscrew union nut 7 and carefully remove the front of the diaphragm housing.
9 - REPLACEMENT OF BOILER COMPONENTS 5 Reconnect the flexible hose, ensuring that the sealing washer is correctly fitted in the union before tightening. 6 Before filling and re-pressurising the heating system - Check the charge pressure in the expansion vessel using a suitable pressure gauge. See section 5.1. 7 Refill the central heating system as described in section 5.2. 9.6 Check valve - Combi 70 1 The check valve is located in the 22 mm heating flow pipe behind the circulating pump.
9 - REPLACEMENT OF BOILER COMPONENTS 9.7a Pressure relief (safety) valve - Combi 90 Note: If there is access to the boiler from above, e.g. it is not fitted below a fixed worktop, use the procedure as for the Combi 70 - See previous section 9.7. If the boiler is below a fixed worktop and there is no access from above, proceed as follows; 1 Shut off the cold water supply to the boiler at the mains stopcock. 2 Drain the central heating system and boiler using the drain cock on the boiler.
9 - REPLACEMENT OF BOILER COMPONENTS Fig.
9 - REPLACEMENT OF BOILER COMPONENTS Fig.
10 - WIRING DIAGRAMS 10.1 Control panel wiring diagram 10.
10 - WIRING DIAGRAMS 10.3 Typical connection of external timer Important: If a remote timer is used, it must be a single channel 240V unit incorporating voltage free output contacts. 10.
Combi 70 & Combi 90 Oil Boilers Burner not firing for hot water. Hot water for short period only Burner oil pressure set too low at oil pump. Incorrect oil nozzle fitted to burner. Burner fires, but not within 90 seconds of hot tap being opened. Boiler thermostat incorrectly set Thermostatic mixing valve incorrectly set. Faulty store thermostat. Pump speed setting too low. Pump is incorrectly fitted. Low water temperature at tap Diverter valve microswitch(es) faulty.
POSSIBLE CAUSE Timeswitch either not set, or not in an 'ON' period. Timeswitch not operating. Faulty timeswitch. Faulty timeswitch switch contacts. Timeswitch OK but not switching boiler on. Heating switch set to 'HOT WATER ONLY'. Room thermostat (if fitted) not calling for heat. Faulty room thermostat. No room thermostat or external timeswitch connected to boiler. Boiler thermostat is set too low. Boiler thermostat faulty. Boiler is underfired. Combustion setting of burner incorrect.
Combi 70 & Combi 90 Oil Boilers Contaminated combustion air (balanced flue). Burner cycles On and Off Excessive combustion air. Insufficient oil flow to burner due to restriction in supply line. Insufficient combustion air supply to burner. Incorrect or faulty nozzle fitted. Fuel pressure too high. Combustion air pipe being heated by flue pipe (balanced flue). Check flue deflector is correctly fitted to terminal. Check flue blanking plate is correctly fitted to terminal.
Insufficient combustion air supply to burner. Flame slow to stabilise on starting Oil leak in supply line or burner. Leak around boiler cleaning door. Burner not correctly fitted on mounting flange. Leakage around flue connection. Faulty boiler thermostat. Oil smells Combustion fume smells Overheat thermostat operating Incorrect or faulty nozzle fitted. Fuel pressure too low. Combustion air pipe being heated by flue pipe (balanced flue). Flue is blocked. Insufficient flue draught.
11.
12 - BURNERSPARE PARTS 12.1 Riello RDB burner - exploded view Combi 70 Key No. Description Riello Part No. Grant Part No. Key No.
13 - HEALTH AND SAFETY INFORMATION Under the Consumer Protection Act 1987 and Section 6 of the Health & Safety at Work Act 1974, we are required to provide information on substances hazardous to health (COSHH Regulations 1988). Adhesives, sealants and paints used in the manufacture of the product are cured and present no known hazards when used in the manner for which they are intended.
14 - EC DECLARATION OF CONFORMITY We declare that the Combi 70 and Combi 90 Oil Boilers equipped with Riello RDB burner approved to EN 267: 1991 satisfy the requirements of the following European Directives:1. 89/336/EEC - Electromagnetic Compatibility Directive Referred to the generic standards EN 55014: 1993, EN 50082: 1: 1992 2. 73/23/EEC - Electrical Equipment Safety Regulations Directive Referred to the generic standard NO: 3260: The Electrical Equipment (Safety) Regulations: 1994 3.
