Low
2 pulses on Worcester Bosch Greenstar 24i Junior

Your boiler is currently in a manual testing mode set to operate at its minimum output, rather than running normally to heat 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.

What the manual says

Manufacturer manual

Not a fault code - Service mode selected to min

From this model's manual
Verified against the Worcester Bosch Greenstar 24i 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 dial or button on the front control panel.Ensure the internal service trigger has not been accidentally toggled.Turn the boiler power off at the fused spur for 30 seconds to perform a hard reset and restore normal operation.

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A cover plan would handle faults like 2 pulses: no call-out fees, no surprise bills.

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