Low
208 on Worcester Bosch Greenstar 12i System

Your boiler is currently running a special manual test mode used by engineers to check settings, rather than operating in its normal heating mode.

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

Appliance in service Test mode (Min/Max)

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual, page 63.
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 or test button on the boiler control panel.Press the button once to exit the test mode and return the boiler to its normal operating position.If it does not switch back, turn the boiler off at the fused spur for 60 seconds and then turn it back on to reset the system.

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