13 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Mexico HE (2013-present) or Mexico Linea
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The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 41-415-20 | Mexico HE 36 | 2005–present |
| 41-429-39 | Mexico HE15 | 2005–present |
| 41-429-65 | Mexico HE18 | 2005–present |
| 41-429-98 | Mexico HE 24 | 2005–present |
| 41-429-99 | Mexico HE 30 | 2005–present |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
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Your boiler has detected a communication issue with the sensor that monitors the temperature of the exhaust fumes, causing it to shut down for safety reasons.
Your boiler is struggling to operate because the electrical supply wires have been connected in the wrong order.
Your boiler has switched off because water produced during the heating process cannot drain away properly, likely due to a blockage in the pipe leading outside.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution to prevent internal damage.
Your boiler has detected that the gases venting out of your home are getting too hot, so it has safely shut itself down to prevent damage or safety issues.
Your boiler has detected that the water inside is getting too hot and has shut itself down as a safety precaution.
Your boiler's internal computer has encountered a critical electronic failure and can no longer control the heating process safely.
Your boiler has become too hot and has automatically shut itself down to prevent damage and ensure safety.
Your boiler has failed to light or maintain a flame, meaning your heating and hot water have stopped working.
Your boiler has shut down because the internal gases have reached a temperature that is dangerously high for the system.
Your boiler has become too hot and has shut itself down for safety purposes.
Your boiler’s internal computer has encountered a critical error and cannot communicate properly with the system.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent damage.
BoilerFaultCodes