Low Service
5 pulses No light on Worcester Bosch 28i Junior

Your boiler is currently stuck in a special testing mode used by engineers rather than a fault condition.

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

Not a fault code Service mode selected to max, press service button to return to normal.

What causes this fault?

This occurs when the service button has been pressed and held, intentionally putting the boiler into a manual test mode. It is physically caused by the control board staying in a 'high fire' setting to allow an engineer to measure gas pressures. The boiler hasn't broken down; it is simply waiting for a command to return to its normal heating program.

DIY fix possible

Locate the service button on the boiler control panelPress the service button once to exit the testing modeEnsure the boiler returns to normal operation with the flashing indicator light now solid or off as per usual

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