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Details about the ISOFAST boiler's capabilities and design.
Initial setup and activation steps for the boiler.
Crucial safety information, controls, and flue system notes.
Step-by-step guide to turning the boiler on.
How to select Summer (hot water only) or Winter (heating & hot water) modes.
Instructions for setting domestic hot water and heating temperatures.
Guide to setting the internal clock and heating schedules.
Information on the boiler's frost protection mechanism.
Steps for safely draining and filling the boiler system.
Guidelines for cleaning the boiler casing.
Warning against unauthorized removal of the boiler casing.
Technical data for heating output, efficiency, and pressure.
Technical data for hot water output and flow rates.
Electrical supply, power consumption, and pump performance data.
Details on how the boiler is packaged and its overall weight.
Diagram and measurements for boiler installation.
Information on compatible heating surfaces and pipe flow calculations.
Guidelines on system water volume and expansion vessel requirements.
Procedures for filling the system and flushing existing installations.
Recommendations for DHW pipework and flow limiting.
Advice for areas with hard water supply.
Labeled diagram of the boiler's internal components.
Identification of parts and connections on the fixing jig.
Guidelines for connecting system pipework to the fixing jig.
Regulations for routing safety valve discharge pipes.
Instructions for gas supply connection and testing.
Recommended space around the boiler for maintenance.
Guidance on cutting holes for the flue system.
Spacing requirements for flue terminals and compartment ventilation.
Legal requirements for boiler installation.
Warning regarding sharp edges on sheet metal parts.
Instructions for installing the top outlet flue kit.
How to calculate lengths for extended flue systems.
Table and method for calculating flue pipe cutting lengths.
Step-by-step guide for assembling the flue system.
Permissible lengths and restrictions for concentric flue systems.
Requirements for earthing and connecting the electrical system.
Guidance on using fused spur boxes or plugs/sockets.
Connecting external controls and room thermostats to the boiler.
Recommendations for purging air from the gas supply.
Procedures for filling the heating system and checking pressure.
Steps to bleed radiators and remove air from the system.
Ensuring the system pressure is within the correct range.
Step-by-step guide to turning the boiler on.
Configuring the boiler for heating and hot water.
How to set the maximum heating temperature.
Adjusting the boiler's heat output in kW.
Configuring maximum heating temperature for different systems.
How the boiler indicates fault conditions.
How the boiler indicates a lack of gas supply.
How low system pressure is indicated and rectified.
Fault codes, telephone symbol, and general safety features.
Safety mechanisms for overheating and freezing.
Steps for setting the gas valve for minimum and maximum pressure.
How to adjust the boiler's built-in bypass.
Steps before performing cleaning and inspection.
How to remove the upper front panel for access.
Accessing internal components via sealed chamber and control panels.
Steps for removing side panels and combustion chamber cover.
Procedures for cleaning and inspecting the burner.
How to clean the heat exchanger.
Ensuring the flue system is clear and secure.
Checking the fan's operation during burner cycles.
How to clean the cold water inlet filter.
Safety precautions and isolation before part replacement.
Steps to replace the DHW thermistor.
Steps to replace the central heating thermistor.
Procedures for replacing the storage vessel thermistor.
Procedures for isolating, refilling, and checking leaks after part replacement.
Steps to replace the fan unit.
How to replace the air pressure switch.
Steps to replace the domestic water flow sensor.
Procedures for replacing the main PCB.
Steps for replacing the circulation pump.
Procedures for replacing the DHW heat exchanger.
Steps to replace the system pressure sensor.
How to replace the gas valve module.
Procedures for replacing the 3-way valve head.
Steps to replace the 3-way valve/bypass housing.
Disconnecting and reconnecting the gas valve module.
Steps for replacing the main gas valve assembly.
How to replace the modulating coil on the gas valve.
Procedures for replacing the central heating safety valve.
Steps to replace the storage vessel safety valve.
Procedures for replacing the primary heat exchanger.
Steps to replace the central heating expansion vessel.
How to replace the high limit thermostat.
Procedures for replacing insulation in the combustion chamber.
Steps for removing and refitting the burner.
How to replace burner injectors.
Steps for replacing the ignition electrode.
Procedures for replacing the flame sense electrode.
Detailed schematic showing all boiler components.
Comprehensive technical data for heating and hot water.
Graphs showing pump performance based on flow rate.
Diagram showing all electrical connections and components.
List of abbreviations and their corresponding component functions.
Essential checks before operating the boiler.
Locations for measuring voltages for electrical testing.
How the boiler indicates and displays faults.
Table of fault codes and their meanings.
Resistance values for thermistors at different temperatures.
List of common spare parts with part numbers.
General| Output Power | 35 kW |
|---|---|
| Fuel Type | Natural Gas |
| Mounting | Wall-mounted |
| Central Heating Output | 35 kW |
| Max working temperature | 80 °C |
| Water pressure | 3 bar |
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