Two red lights flash rapidly Low

Worcester Bosch Two red lights flash rapidly Fault Code

Also written as TWOREDLIGHTSFLASHRAPIDLY — same fault.

The Worcester Bosch Two red lights flash rapidly fault code means: your boiler is currently set to a special testing mode used by engineers to check its performance, rather than operating in its normal heating mode.. It appears on 3 Worcester Bosch models in our database.

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

DIY fix possible

Locate the service mode switch or button on the boiler control panel.Ensure it is set back to the 'Auto' or 'Normal' operating position.Turn the boiler off at the fused spur for 30 seconds and then back on to reset the system.

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Worcester Bosch models that show the Two red lights flash rapidly fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch Two red lights flash rapidly fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026