22 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 pipes that vent exhaust gases outside, meaning it has safely shut down to prevent the buildup of fumes indoors.
Your boiler's flue assembly is configured using a specific 45-degree elbow piece, which is a structural setting rather than an active fault.
Your boiler is failing to light the flame because the internal electrical connection responsible for triggering ignition is likely faulty or disconnected.
Your boiler has detected an internal issue with how heat is transferred between the burner and your water, meaning it has shut itself down to prevent damage.
Your boiler has detected an issue with the protective insulation lining inside the combustion chamber, which is a safety-critical part that keeps the heat contained.
Your boiler is struggling to remove trapped air from the system, which can prevent heat from circulating properly to your radiators.
Your boiler's water circulation pump or its electrical connection has failed, meaning your heating and hot water cannot function because the system can no longer push hot water around your radiators and taps.
Your boiler is detecting an issue with the internal water pressure management, usually caused by a drop in pressure or a flat expansion vessel.
Your boiler is struggling to detect or control the flow of hot water, which likely means you will have no hot water coming out of your taps or shower.
Your boiler has temporarily shut itself down because the internal water temperature got too high.
Your boiler has detected an issue with the internal seals designed to keep combustion gases trapped safely inside the unit.
Your boiler has failed to ignite because it cannot detect a flame, meaning it has safely shut itself down to prevent gas from building up.
Your boiler is failing to ignite because it cannot correctly access or regulate its gas supply.
Your boiler has temporarily stopped working because a temperature sensor has come loose or lost connection.
Your boiler has lost the ability to properly detect the flame, so it has safely shut down to prevent gas from flowing without a fire.
Your boiler is having trouble venting exhaust gases correctly, likely because the external flue pipe configuration is not communicating properly with the sensors.
Your boiler is struggling to clear exhaust gases due to an issue with the pipes that lead to the outside, which is preventing the system from running safely.
Your boiler has detected an issue with the pipes that vent exhaust gases outside, meaning it cannot safely clear its fumes.
Your boiler has detected an internal issue with how a component is physically secured, which is preventing it from operating safely.
Your boiler is struggling to read its own water temperature, so it has safely shut itself down to prevent potential overheating.
Your boiler is struggling to manage the water pressure within the system, which typically means a small internal pressure-balancing component is failing or requires adjustment.
Your boiler's main electronic brain is experiencing an internal communication or hardware error, which causes the appliance to safely lock out.
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BoilerFaultCodes