High
90 on Viessmann Vitodens 200-W B2HA-35

Your boiler has detected a faulty temperature reading inside its system, so it has likely paused to protect itself, and a qualified engineer should check it.

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

Short circuit, temperature sensor

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2ha B2ka 5772909 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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Related fault codes

F28View →F29View →F91View →

All 83 fault codes on the Vitodens 200-W B2HA-35

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

4C9A9b9C9E9F1018192028303840444850515859919293949899A3A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCFd6d7d8dAdbdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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