High
F9 on Saunier Duval SD Themaplus Condens F 30 E

Your boiler is struggling to detect the water level inside the system because the sensor that monitors it is disconnected or experiencing a communication error.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Water pressure sensor fault - Faulty sensor connection, Check wiring

From this model's manual
Verified against the Saunier Duval/Saunier Duval Themaplus Condens F30e 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 18 fault codes on the SD Themaplus Condens F 30 E

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

F1F4F5F6F7F8F10F11F13F16F18F19F20F23F26F28F29

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