16 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Mexico HE
The fault code is already on your display
Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
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 |
|---|---|---|
| 41-392-81 | Mexico Super CF 445 | 2001–2006 |
| 41-392-82 | Mexico Super CF 455 | 2001–2006 |
| 41-392-83 | Mexico Super CF 465 | 2001–2006 |
| 41-392-84 | Mexico Super CF 475 | 2001–2006 |
Tap any card for details
Your boiler is unable to ignite the small pilot flame required to start the main heating process.
Your boiler is failing to keep its small pilot flame burning, which prevents the main heating unit from starting up.
Your boiler has started part of the ignition process and has a pilot light, but the main burner is failing to ignite to provide heat.
Your boiler is unable to start the small flame needed to ignite the main burner, meaning your heating and hot water will not work.
Your boiler's pilot light is going out as soon as you let go of the ignition button, preventing the main burner from starting up.
Your boiler has successfully lit the small pilot flame, but the main burner is failing to ignite to provide heat or hot water.
Your boiler has managed to light the small pilot flame, but the main gas burners are failing to ignite to heat your home.
Your boiler is likely having trouble reading the temperature setting because the control knob is faulty or incorrectly positioned.
Your boiler has switched itself off because it got too hot, and it needs to cool down before it can be restarted.
Your boiler has failed to light because it cannot get the gas supply it needs to start the heating process.
Your boiler is failing to light the burner because the electrical cable responsible for creating the igniting spark is faulty or disconnected.
Your boiler is failing to ignite because it cannot detect or receive a steady supply of gas to create a flame.
Your boiler has detected an issue with the internal flue vent that prevents it from clearing exhaust gases safely, causing it to shut down to protect your home.
There is a possible smell or leakage of gas which could lead to fire or explosion if not addressed immediately.
Your heating system is losing water, which means there is likely a leak or a failing pressure relief valve causing the boiler to stop working correctly.
Your boiler has shut down because wind or a blockage is pushing harmful exhaust fumes back down the chimney instead of letting them escape outside.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes