Medium
Lt on Johnson Starley C10d

Your heater is temporarily shutting 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 all warm air grilles/vents are open and not blocked by furniture or curtainsInspect the air filter and clean or replace it if it is dustyTurn the heater off and back on to reset once it has cooled down

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