Ideal Mexico Super CF3 40-80 Fault Codes

Regular Natural Gas 11.7-23.4 kW 1997-2003 Discontinued

GC Numbers: 41-391-4241-391-4341-391-4441-391-4541-391-46

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 →

Most common fault codes

Code	Severity	Plain English	DIY
49	High	Your boiler is unable to start the small flame needed to ignite the main burner, meaning your heating and hot water will not work.	Engineer
50	High	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.	Engineer
51	High	Your boiler has successfully lit the small pilot flame, but the main burner is failing to ignite to provide heat or hot water.	Engineer
52	High	Your boiler has managed to light the small pilot flame, but the main gas burners are failing to ignite to heat your home.	Engineer
Boiler Overheat Thermostat	High	Your boiler has switched itself off because it got too hot, and it needs to cool down before it can be restarted.	Yes
Loss of system water pressure	High	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.	Yes
TTB Downdraught Thermostat	Emergency	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.	Engineer

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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