115 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an issue with the gas pressure or a component failure and has shut down as a safety precaution.
Your boiler has detected an internal communication error and has shut itself down as a safety precaution.
Your boiler has shut down because it is struggling to discharge exhaust fumes safely or is detecting a significant lack of air flow.
Your boiler has shut down because it is struggling to discharge exhaust fumes safely or is detecting a significant lack of air flow.
Your boiler has stopped working because the burner isn't lighting correctly, likely due to a problem with the internal airflow or the ignition system.
Your boiler has shut itself down as a safety precaution because it has detected an overheating issue within the system.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected that the hot water cylinder is connected directly to the unit, but there is likely a communication error or a faulty sensor preventing it from heating your water correctly.
Your boiler is confused about where your hot water tank is located within the system pipework, often due to a setup error or a sensor problem.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler's internal pump or fan is reporting an incorrect speed setting, which is usually a technical communication error between the internal computer and the parts that move water or air.
Your boiler's internal pump for hot water is stuck running at full speed, which usually means there is a communication error or a part is beginning to fail.
Your boiler is providing an advisory notification about how much power it is using to heat your hot water, rather than indicating a mechanical breakdown.
Your boiler is telling you that it has defaulted to its maximum power setting for heating your hot water because it has encountered a configuration memory error.
Your boiler has detected a sequence error or a flame signal where there shouldn't be one, causing the burner to shut down completely for safety.
Your boiler is having a communication problem regarding the time settings between its internal control parts.
Your boiler is having difficulty communicating the correct time to other parts of the heating system or external controls.
Your boiler has been incorrectly set to a multi-boiler configuration even though it is operating as a single unit.
Your boiler system is communicating with multiple other boilers through a shared exhaust pipe, and it has detected a technical configuration error in that connection.
Your boiler has encountered a technical internal error specifically relating to its main electronic control board which is preventing it from running.
Your boiler’s internal control system has encountered a processing electronic fault, meaning it cannot properly communicate with its own internal components.
Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
Your boiler has detected a sequence error or a flame signal where there shouldn't be one, causing the burner to shut down completely for safety.
Your boiler has detected an error with its internal temperature settings or the control unit, which may cause it to stop providing heating or hot water correctly.
Your boiler has detected an incorrect setting or a communication error regarding the minimum water temperature required when an external control system asks for heat.
Your boiler has stopped working because its internal control computer has lost its configuration settings or is unable to communicate with its safety sensors.
Your boiler is currently undergoing a pre-set maintenance test or a specialized calibration check that lasts between 5 and 60 minutes.
Your boiler has lost communication with one of its internal control modules or an external smart accessory, causing it to use temporary backup settings.
Your boiler is notifying you that it has reached a specific temperature difference limit you have set, which usually means the water is heating up faster or slower than expected.
Your secondary heating circuit is not reaching the required temperature difference to operate correctly, likely due to a flow or sensor issue in that specific zone.
Your boiler is getting too hot too quickly and is shutting itself down to prevent damage.
Your boiler's computer has become stuck in a repeating internal test sequence and is failing to move into its normal heating mode.
Your boiler is receiving a specific signal from an external control or accessory that it doesn't currently know how to handle.
Your boiler is receiving a conflicting signal from an external control or accessory that is telling the pumps how to run incorrectly.
Your boiler has failed to ignite or stay lit, meaning your heating and hot water have stopped working.
Your boiler's computer screen and main control board are having trouble communicating with each other.
Your boiler has detected a short circuit in the sensor that monitors your hot water temperature, meaning it can no longer accurately heat your tap water.
Your boiler is struggling to monitor the temperature outside, which is preventing it from adjusting your heating efficiently.
Your boiler is struggling to monitor the temperature of a specific part of your system's pipework, which may cause your heating to run less efficiently or stop working correctly.
Your boiler is struggling to accurately measure the water temperature in a specific part of your heating system, which may cause your heating to run inefficiently or not at all.
Your boiler has detected a general internal fault that is preventing it from running properly, often linked to an issue with the main control system or a signal error.
Your boiler has detected a communication problem with the pump that circulates hot water around your taps, which may cause delays in getting hot water or stop it altogether.
Your boiler is having trouble communicating with the external pump that circulates hot water to your radiators, meaning your heating may not turn on correctly.
Your boiler is having trouble communicating with the pump that fills your external hot water tank, meaning your hot water supply may be affected.
Your boiler is confused because it thinks it should be connected to a solar heating system that it cannot find.
Your solar heating system is experiencing a communication error or fault, which may affect how efficiently your water is heated.
Your boiler is having trouble communicating with the solar heating control module during its automatic setup process.
Your boiler is experiencing an issue where it cannot properly monitor or control the temperature of your hot water.
Your boiler's hot water sensor is reporting an unusually high temperature range, which may prevent your hot water from heating correctly.
Your boiler is struggling to heat your hot water tank because it cannot detect or communicate with a required external sensor or control module.
Your boiler is notifying you that a specific setting for your hot water temperature has been manually adjusted or requested.
Your boiler has detected an issue with the sensors that monitor the temperature of your hot water cylinder, which may lead to inconsistent water temperatures.
Your boiler has detected a minor internal setting inconsistency regarding when it should start heating, but it is unlikely to stop your hot water or heating from working.
Your boiler is struggling to reach the temperature requested for your hot water because the internal settings are set too high or a sensor is misreading.
Your boiler is getting much hotter than it should while trying to heat your water, which usually means the heat isn't transferring correctly to your tank.
Your boiler's internal pump is failing to stay on long enough to safely dissipate heat after the burner turns off, which can cause the system to overheat.
Your boiler's pump is set to run for a specific amount of time after the heating switches off to help the system cool down safely.
Your boiler has detected an issue with the internal pump's operation, causing it to run for a short safety cooling period before pausing.
Your boiler is failing to communicate properly with the equipment used to heat your hot water tank, meaning you may lose hot water.
Your boiler is performing a routine daily check to ensure the internal pump and components are not seized up.
Your boiler is notifying you that a specific pre-set service interval or scheduled maintenance time has elapsed and a routine check-up is now required.
Your boiler has detected an internal electronic error that suggests the main control unit is beginning to fail, which may cause your heating and hot water to become unreliable.
Your boiler has lost communication with the internal valve that directs heated water to either your radiators or your hot water tank, meaning your system cannot function correctly.
Your boiler is having trouble directing water to the right place, meaning you might not have any heating or hot water until it is fixed.
Your boiler is having trouble directing hot water between your taps and radiators due to a mechanical issue with a internal valve.
Your boiler is struggling to switch the flow of heated water between your radiators and your hot water taps because of an internal valve malfunction.
Your boiler has likely detected an internal configuration issue or a fault with the control board that manages your hot water settings.
Your boiler is having trouble communicating with the solar heating controls, which may prevent your hot water from reaching the desired temperature.
Your boiler is notifying you that your hot water circulation pump is currently active based on its programmed schedule, which may be an advisory rather than a breakdown.
Your boiler is switching itself off because it is struggling to reach the correct temperature while trying to heat your hot water tank.
Your boiler is having trouble heating your hot water cylinder because a sensor has detected an unusually high temperature or a fault during the heating process.
Your boiler is notifying you that the hot water circulation pump is currently active based on its set schedule, though it may indicate a minor communication lag with the sensor.
Your boiler is switching itself off unexpectedly while trying to heat your hot water tank because a temperature sensor is detecting an unusual reading.
Your boiler has detected that hot water is being heated when it shouldn't be, which is usually caused by a faulty sensor or a sticking internal valve.
Your boiler's hot water circulation pump is currently active based on its programmed timer settings.
Your boiler is notifying you that the hot water cylinder's circulation pump is running on a preset timed cycle to prevent legionella or keep the water warm, rather than responding to a specific heating demand.
Your boiler communication module has a permanent fault that is preventing the system from talking to its controls correctly.
Your boiler's internal communication system is failing to connect with other smart controls or external heating modules.
Your boiler is having difficulty communicating with its internal smart connection module, usually meaning there is a minor electronic glitch or a connection has come loose.
Your boiler is having trouble communicating with its internal control modules or multiple boiler system systems, which may stop it from operating correctly.
Your boiler's internal communication system has identified an addressing conflict between different control units on the network.
Your boiler's internal control panel is having a communication error and is struggling to coordinate with other linked components in the system.
Your boiler's main control unit has detected an internal communication error and is struggling to manage the various components of the heating system.
Your boiler is experiencing a communication error between its control system and the temperature sensors, meaning it cannot accurately monitor the water temperature.
Your boiler has detected a communication error with its internal sensors or control unit that has lasted for more than five seconds.
Your boiler is pausing temporarily to prevent it from switching on and off too frequently, which helps protect the internal components.
Your boiler has been manually switched to a mode where it only provides hot water and has turned the central heating off for the season.
Your boiler is notifying you that it has automatically switched between summer and winter mode based on the external temperature.
Your boiler is having trouble communicating with its external radio clock module, meaning it may not know the correct time or date for your heating schedule.
Your boiler is having trouble synchronizing its clock with other connected parts of your heating system.
Your boiler is operating normally, but the display settings have been changed or reset to show temperatures in Celsius.
Your boiler is simply displaying the temperature in Fahrenheit instead of Celsius due to a settings change.
Your boiler is struggling to adjust the heating temperature correctly in response to changes in the weather outside.
Your boiler is receiving an unusual signal from the outdoor temperature sensor, likely due to a minor communication error or a faulty sensor outside your home.
Your boiler is having trouble communicating with an external control accessory, meaning some remote settings or external commands might not be working as expected.
Your boiler has detected an external control conflict where a heating setting is trying to communicate with a part of the system that isn't configured to receive it.
Your boiler is experiencing a communication issue with the accessory that controls different temperature zones in your home, often caused by a temporary wiring hitch or a sensor problem.
Your boiler's control system is receiving conflicting instructions regarding how your heating cycles should run across your different radiators or zones.
Your boiler is trying to connect to a remote control accessory that it cannot find or which has lost power.
Your boiler has detected an issue communicating with its remote control or internet connection module during the initial setup process.
Your boiler is noting a change in how it reads the outside temperature, but it is typically just an internal setting update and should not stop your heating.
Your boiler is receiving the outdoor weather information from another connected device on your home network rather than its own direct sensor.
Your boiler is having trouble communicating with the outdoor temperature sensor, which helps the system run more efficiently based on the weather.
Your boiler is experiencing a communication error with an external remote monitoring system, meaning the central hub cannot correctly read your heating data.
Your boiler is confused because it doesn't know which type of heating system it is supposed to be controlling.
Your boiler has lost communication with its external thermostat or control unit, meaning it may not know when to turn your heating on or off.
Your boiler has lost communication with its remote control thermostat, meaning it cannot receive temperature instructions.
Your boiler is having trouble communicating with the wall-mounted room controller and may need a simple reset to re-establish the connection.
Your boiler has sensed that the internal pump is malfunctioning or water is not circulating correctly, which has caused the system to stop as a safety precaution.
Your boiler is currently ignoring the standard priority for hot water and is attempting to provide heating and hot water at the same time, which may result in lukewarm water or poor heating performance.
Your boiler is currently focused on heating your hot water tank, so it has temporarily paused the central heating to ensure you have enough hot water.
Your boiler is likely experiencing a communication or pump error where it is struggling to switch between heating your house and heating your hot water tank.
Your boiler is automatically managing its pump based on the outdoor temperature to prevent your pipes from freezing.
Your boiler has detected that the water pump is likely stuck or not moving water correctly, which means the system cannot heat up safely.
BoilerFaultCodes