25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Eco2
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Your boiler is failing to light the internal flame, which means it cannot provide heat or hot water.
Your boiler has detected that it is running too hot and has automatically shut down to prevent internal damage.
Your boiler has detected that the internal component responsible for clearing spent gases is not operating, so it has safely shut down to prevent unsafe operation.
Your boiler has detected a loose or faulty electrical connection to the internal gas control system, which prevents it from firing safely.
Your boiler has lost the ability to accurately measure the temperature of the water being sent to your radiators, so it has shut down to prevent the system from overheating.
Your boiler is struggling to accurately measure the temperature of your hot water, which means it has stopped providing it to prevent system errors.
Your boiler has stopped because the water pressure inside the system has dropped too low or risen too high, preventing it from heating safely.
Your boiler has switched itself off because the water level inside the heating system has dropped too low.
Your boiler is struggling to accurately measure the temperature of your hot water cylinder because there is an issue with the sensor connection or the sensor itself.
Your boiler's computer is struggling to read its own settings, which prevents it from starting up correctly.
Your boiler has detected that the internal fan is moving too slowly or too fast, so it has shut down to prevent unsafe operation.
Your boiler has detected a flame signal even though it is supposed to be switched off, which is a safety concern that prevents it from restarting.
Your boiler's control panel is registering a button as being permanently pressed or stuck, which is preventing it from operating correctly.
Your boiler is overheating because it cannot move the hot water away from the heating unit fast enough.
Your boiler is struggling to pump water around your radiators, so it has turned itself off to prevent overheating.
Your boiler has detected that a temperature sensor in the exhaust system is sending incorrect information, so it has safely shut down to prevent damage.
Your boiler has lost its connection to its wall controller or thermostat, meaning it cannot receive signals to turn on your heating or hot water.
Your boiler has detected that the electricity supply coming into your home is weaker than it needs to be to run the system safely.
Your boiler has stopped because the internal flame has unexpectedly gone out while it was trying to heat your water.
Your boiler is repeatedly struggling to keep its internal flame lit while trying to run.
Your boiler has lost the connection to an optional external temperature sensor, which usually means a wire has come loose or the sensor has been disconnected.
Your boiler has detected that the exhaust gases are getting too hot and has automatically slowed down to protect itself from overheating.
Your boiler has lost its wireless connection to the heating controller, so it no longer knows when to switch on or off.
Your boiler has detected that it is getting too hot and has safely shut itself down to prevent damage.
Your boiler's small starter flame is failing to stay on, which prevents the main burner from igniting and stops your heating and hot water from working.
BoilerFaultCodes