9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost communication with the weather sensor located outside your home, which may cause it to heat your radiators less efficiently.
Your boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot heat your home or water safely.
Your boiler has stopped working because it cannot correctly measure the temperature of the water coming back into the system.
Your boiler has lost communication with the hot water temperature sensor, meaning it cannot accurately heat your water.
Your boiler's internal computer system has lost connection with its controls or sensors, preventing it from understanding how to heat your home.
Your boiler has detected that the water pressure is either too low or too high for it to operate safely, or the sensor that monitors this pressure has lost its connection.
Your boiler is currently running an automatic air-bleeding cycle to remove bubbles from the system, which typically happens after a power cut or when first switched on.
Your boiler has switched itself off because it has detected an internal temperature that is too high to operate safely.
Your boiler has stopped working because the internal fan, which safely pushes exhaust fumes outside, is not spinning at the correct speed.
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BoilerFaultCodes