Medium
1023 W on Worcester Bosch Greenstar 8000 F GR8700iF 35 R

Your boiler has been running continuously for too long and has safely paused itself as a precaution.

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

Maximum run time including standby time reached

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Wb 47850 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

All 99 fault codes on the Greenstar 8000 F GR8700iF 35 R

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

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