14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Isomax Condens
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Your boiler has stopped working because it cannot properly clear away exhaust fumes or draw in fresh air to burn gas safely.
Your boiler is failing to light the gas or cannot tell that the flame has successfully ignited, meaning it won't be able to provide heating or hot water.
Your boiler has got too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler's internal temperature sensor has stopped sending the correct signal, meaning the system doesn't know how hot the water is and has shut down for safety.
Your boiler is struggling to accurately measure the temperature of your hot water, which usually means it cannot provide consistent or safe water temperatures.
Your boiler's hot water storage tank sensor is failing to report the correct temperature, which might lead to inconsistent or no hot water.
Your boiler has lost track of the water pressure inside the system because the internal sensor is failing or sending an incorrect signal.
Your boiler has stopped working because the fan that helps remove waste gases is not spinning correctly.
Your boiler's control panel has lost communication with the internal computer, meaning it cannot receive your instructions on how to heat your home.
Your boiler's internal computer has developed a fault and can no longer control the heating system correctly.
Your boiler has shut down because a temperature sensor has detected that the water inside is getting too hot, likely due to a circulation problem.
Your boiler has detected a problem with how it controls the gas supply, preventng it from lighting safely.
Your boiler's internal computer parts are failing to talk to each other, meaning the system cannot receive the instructions it needs to work.
Your boiler is failing to light the flame, which is likely due to a lack of gas reaching the unit or a problem with the ignition system.
BoilerFaultCodes