D.91 Low
Your boiler is providing a status update about its connection to an outdoor temperature sensor used for the radio clock signal.
Technical description: DCF status with connected external probe
Typical repair cost: £0 (including labour)
DIY fix possible
No action is required as this is a status code, not a breakdown fault.Check that the display shows the correct time and date.Ensure nothing is obstructing the external sensor on the outside wall.
Protect yourself from future repair bills
A boiler cover plan would cover faults like D.91 — no call-out fees, no surprises.
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