9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is struggling to move heat away from the unit efficiently, causing it to slow down to protect itself from overheating.
Your boiler has lost the ability to read the temperature from an external sensor, which is preventing it from heating your home properly.
Your boiler has detected an issue with the water circulation system, meaning it cannot effectively move heat around your home or to your taps.
Your boiler has detected that the water pressure inside the system is too low to operate safely.
Your boiler has detected a problem with the flow of water inside the unit, preventing it from heating up correctly.
Your boiler has detected an issue with the water temperature or flow sensor, meaning it has shut down to protect itself from overheating.
Your boiler has detected that the water pressure inside the heating system is too low to operate safely.
Your boiler has detected an issue with the water pressure system, which is preventing it from heating your home or water.
Your boiler has detected an issue with the water pressure or a problem with the temperature sensor, causing it to lock out for safety.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes