18 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost connection with the sensor that monitors the temperature of your hot water cylinder, meaning it may not know when to heat your water.
Your boiler has stopped working because the internal fan, which safely helps the system breathe and clear exhaust gases, is not spinning correctly.
Your boiler is struggling to detect the flame needed to heat your water, even if the burner has successfully lit.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators.
Your boiler has detected that one of the buttons on the control panel is stuck or faulty, preventing you from changing settings.
Your boiler has detected that water is not moving through the system quickly enough to prevent it from overheating.
Your boiler has detected a problem with the sensor that monitors exhaust gases, and it has shut down for safety purposes.
Your boiler has lost its connection with the thermostat or control panel, meaning it cannot receive instructions to turn on or off.
Your boiler has stopped working because the electricity supply coming into the unit has dropped below the minimum level required to operate safely.
Your boiler has started an ignition process but lost its flame unexpectedly, causing the system to shut down for safety.
Your boiler has lost the signal that confirms a flame is burning, so it has shut down for safety.
Your boiler is overheating because the water is not flowing through the system as quickly as it should.
Your boiler has stopped running because an external safety thermostat has detected that the water temperature has become too hot.
Your boiler is still working but cannot reach its full power, meaning your radiators might not get as hot as they should.
Your boiler has shut down because the water returning from your radiators has become too hot, usually caused by a circulation problem.
Your boiler has lost its wireless connection with your thermostat or remote control, meaning they can no longer talk to each other to manage your heating.
Your boiler has detected a problem with the sensor that monitors water temperature as it returns from your heating system, causing the unit to stop running for safety.
Your boiler has stopped running because it senses that even though the burner is lit, the water inside isn't getting any warmer.
BoilerFaultCodes