Low
5 pulses on Worcester Bosch 28i Junior

Your boiler is currently in a manual testing mode set to operate at its maximum output, rather than running a normal heating or hot water cycle.

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.

What the manual says

Manufacturer manual

Not a fault code - Service mode selected to max

From this model's manual
Verified against the Worcester Bosch 28i Junior 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

Locate the service mode switch or dial on the internal control panelRotate the dial back to the 'Auto' or standard operating positionReset the boiler by pressing the reset button to return to normal operation

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