Low
Fd on Worcester Bosch Highflow 550 CDi

Your boiler's reset button has been held down for too long, causing the control panel to lock out as a safety precaution.

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

Reset button has been pressed for more than 15 seconds

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Highflow 550 Cdi 4740691 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

Switch off the power to the boiler using the main isolation switch or fuse spur.Wait for 60 seconds to allow the internal electronics to fully reset.Switch the power back on and do not touch the reset button unless a specific fault code is displayed.

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All 24 fault codes on the Highflow 550 CDi

Seeing a different code? Every code this model can display, in one place.

6AA1A5A7A8b1b2b3b4b5b6b7C6d3d5d6E2E9EAF0F1F7FA

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