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Boiler's automatic operation for domestic hot water and central heating.
Accessing and identifying boiler controls on the front door.
Explanation of Heating and Boiler On/Off switches.
Step-by-step procedure for lighting the boiler.
Instructions for turning the boiler off for short and long periods.
Troubleshooting steps for a burner that fails to ignite.
How the boiler provides domestic hot water and factors affecting flow.
How the boiler operates the central heating system and thermostat settings.
Advice on optimizing hot water performance and central heating.
Notes on controls, safety, ventilation, cleaning, and electricity supply.
Information on fuel types (Kerosene, Gas Oil) and handling.
Requirements for the electrical supply and safety warnings.
Table of technical specifications for Combi 70 and Combi 90 models.
Performance data for Kerosene fuel.
Performance data for Gas Oil fuel.
Guidance on setting air dampers for optimal combustion.
Diagram and dimensions for boiler installation.
Diagram illustrating the boiler's water circuits and components.
Overview of the Combi 70 & 90 boilers and their design.
List of relevant building regulations and standards for installation.
Details on boiler and flue kit packaging and delivery.
Requirements for fuel storage, pipes, single/two pipe systems, Tiger Loop.
Requirements for the electrical supply and safety.
Requirements for permanent air supply for combustion and ventilation.
Guidance on installing conventional flue systems.
Step-by-step instructions for connecting a conventional flue.
Overview of available balanced flue kits and their specifications.
Recommendations for frost protection using thermostats.
Guidelines for siting the boiler and required clearances.
Details on connecting water pipes for Combi 70 and Combi 90.
Requirements for sealed central heating systems.
Information on hot water flow, pressure, and hardness.
Instructions for using the water hardness test kit.
Explanation of how the boiler operates for heating and hot water.
Steps for unpacking the boiler and its components.
Instructions for preparing the wall for flue installation.
Fitting instructions for high level and vertical balanced flues.
Step-by-step guide to making water connections for Combi 70 and 90.
Instructions for fitting a low level square balanced flue.
Guide to connecting the boiler's power supply.
Wiring instructions for external remote timeswitches.
Installation of a 24-hour mechanical timer.
Installation of a 7-day electronic timer.
Steps for connecting the fuel supply to the burner.
Information on expansion vessel charge pressure and testing.
Procedure for filling and venting the heating system.
Step-by-step procedure for commissioning the boiler.
Key information and demonstrations for the user.
Essential checks before performing boiler servicing.
Steps for dismantling the boiler for servicing.
Instructions for cleaning the Combi 70 boiler.
Instructions for cleaning the Combi 90 boiler.
Steps for cleaning the boiler's burner and electrodes.
Procedure for replacing the circulating pump.
Steps to replace the plate heat exchanger and diverter valve.
Replacing the diverter valve diaphragm.
Procedure for replacing the thermostatic mixing valve.
How to replace the expansion vessel.
Replacing the check valve in the Combi 70.
Replacing the check valve in the Combi 90.
Replacing the safety valve on the Combi 70.
Replacing the safety valve on the Combi 90.
Replacing the automatic air vent on the Combi 70.
Replacing the automatic air vent on the Combi 90.
Diagram of Combi 70 water components and connections.
Diagram of Combi 90 water components and connections.
Wiring diagram for the boiler's control panel.
Diagram showing the functional flow of electrical signals.
Wiring diagram for connecting an external timer.
Wiring diagram for the Grant mini programmer.
Troubleshooting domestic hot water problems.
Troubleshooting central heating and hot water issues.
Common boiler faults, causes, and actions.
Specific fault finding guide for the Riello RDB burner.
Exploded view of the Riello RDB burner with parts list.
Information on insulation, sealants, and fuel hazards.
Declaration of compliance with European directives.
General