Low
Pr12 on Johnson Starley Warmcair DW

Your boiler is notifying you that its maximum power setting has been manually limited, often for efficiency or to match the specific size of your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Parameter selection for reducing the rated net input

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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