Low
dd on Viessmann Vitodens 242-F FB2B

Your boiler is temporarily unable to read the temperature of your main heating area because a connection to its temperature sensor has come loose or broken.

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

Lead break, room temperature sensor, heating circuit 1 (without mixer)

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 242 F Fb2b 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

d1View →d2View →d3View →

All 66 fault codes on the Vitodens 242-F FB2B

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

9A9C9E9F58599294A2A4A7A8A9b0b1b4b5b7b8bAbbbCbdbEbFC1C2C3C4CdCFd6d7d8dAdbdCdEdFE0E1E3E4E5E6E7E8EAEbECEdEEEFF0F1F2F3F7F8F9FAFCFdFEFF

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