Medium
57 on Johnson Starley C10d

Your heater has automatically shut itself down because it is getting too hot and needs to cool down for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

In order to limit the warm air temperature the heater will shut off the burner and Lt will be displayed in the centre of the display.

DIY fix possible

Check that all warm air vents and registers are open and not blocked by furniture or curtains.Inspect the air filter and clean or replace it if it is dusty or clogged.Ensure the return air grille is clear of obstructions to allow proper airflow.

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