14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: CDi Classic
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Your boiler is struggling because the internal water pump is stuck or cannot circulate water properly, preventing your heating and hot water from working.
Your boiler has lost the ability to accurately measure the temperature of the hot water it produces, so it has shut down to prevent overheating.
Your boiler has lost its connection to your room thermostat or control panel, meaning it no longer knows when to turn your heating on or off.
Your boiler's internal computer is failing to communicate with its memory chip, causing the system to lock out for safety reasons.
Your boiler has stopped working because the internal fan isn't spinning fast enough to safely clear away exhaust fumes.
Your boiler has detected that the internal fan is spinning faster than it should, which has caused the system to shut down for safety.
Your boiler is struggling to breathe because the internal fan is not spinning fast enough to safely clear exhaust gases, so it has safely shut itself down.
Your boiler is struggling to read its own temperature because a component that monitors the heating water has stopped working correctly.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage to the system.
Your boiler is trying to start but the flame is not catching, meaning you currently have no heating or hot water.
Your boiler's computer is experiencing a general internal glitch that is preventing it from running safely.
Your boiler has detected a flame signal when it is not supposed to be running, which suggests a sensor or electronic error that requires professional attention to ensure safety.
Your boiler has detected that a flame is still burning even though it has commanded the gas to turn off.
Your boiler is simply indicating that the reset button was pressed when no actual fault was present, so it is just waiting for a normal restart.
BoilerFaultCodes