13 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Mexico HE or Mexico Slimline
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Your boiler is unable to start the small pilot flame needed to ignite the main heating system.
Your boiler is failing to keep the pilot light burning after you let go of the ignition button, meaning the heating cannot start.
Your boiler has successfully lit its pilot light, but the main burner is failing to ignite because it is not receiving the main supply of gas.
Your boiler's pilot light is failing to stay ignited after you try to light it, meaning the main burner cannot start to provide heat.
Your boiler has managed to start the small pilot flame, but the main burner fails to ignite to provide full heating.
Your boiler is struggling to clear fumes properly because an internal metal part designed to guide exhaust gases is likely out of position or damaged.
Your boiler has detected an issue with the internal metal plate that manages airflow, which may prevent the unit from venting exhaust gases safely.
Your boiler has failed to ignite or stay lit, which means you currently have no heating or hot water, and a gas-safe engineer is required to investigate the internal ignition system.
Your boiler is failing to detect a flame because the internal component responsible for controlling the fuel supply is not operating correctly.
Your boiler is losing the water it needs to heat your home, which is likely caused by a slow leak somewhere in your radiators or pipework.
Your boiler is receiving electrical power and is currently on standby or ready to operate.
Your boiler is currently trying to light the flame, and the light should turn off as soon as the heater starts working normally.
Your boiler has become too hot and has automatically shut itself down to prevent damage or safety issues.
BoilerFaultCodes