Medium
Two red lights flash rapidly on Worcester Bosch 28 i SI

Your boiler is currently stuck in a manual testing mode often used by engineers and is not operating in its normal heating or hot water setting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Appliance is in MAX or MIN mode (Service Mode).

From this model's manual
Verified against the Worcester Boiler 28si 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 two buttons on the front control panel marked with a flame icon and an ECO or central heating icon.Press and hold the 'eco' button for approximately 10 seconds until the rapid flashing stops.The boiler should revert to its standard operating mode or reset itself automatically.

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