Low Information
9.A on Worcester Bosch Greenstar CDi Compact

Your boiler's control panel has been set to stay on permanently, which means it isn't following your usual heating schedule or thermostat settings.

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

Operation mode permanent

What causes this fault?

This code appears when the boiler's internal service or manual override mode has been activated, telling the unit to ignore external thermostats. It often happens if a setting was accidentally changed during a service or if the control dial was left in the ‘on’ position rather than being set to follow your timer. Because the boiler is receiving a permanent 'run' signal, it will continue to heat until you manually switch it back to its automatic mode.

DIY fix possible

Locate the main control dial on the front of the boiler.Turn the dial away from the maximum 'permanent on' setting to a lower number or your desired temperature.Check your external thermostat or programmer to ensure it is now back in control of the heating.

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