Medium
304 on Atag i40C

Your boiler has been manually reset too many times in a short period and has temporarily locked itself for safety.

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

Too many resets

From this model's manual
Verified against the Atag/Atag I Series Combi 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

Turn off the power supply to the boiler at the fused spur switchWait for at least 30 secondsTurn the power back on to clear the software lockout

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Related fault codes

101View →133View →151View →

All 16 fault codes on the i40C

Seeing a different code? Every code this model can display, in one place.

1P4101102104108109110112114140*201203303501612

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