Medium
Lt on Johnson Starley C16u

Your heater is temporarily turning itself off because it is getting too hot and needs to cool down to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

What the manual says

Manufacturer manual

Heater will shut off the burner in order to limit the warm air temperature.

From this model's manual
Verified against the Johnson Starley C16u installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check all warm air vents throughout the house to ensure they are fully open and not obstructed by furniture or curtains.Inspect the air filter and clean or replace it if it is clogged with dust.Ensure the return air grille is clear and not blocked by household items.

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