Low
20 on Viessmann Vitodens 200-W B2HA-26

The boiler has lost its reading of how hot the water leaving it is, so it is working by estimate, which usually means heating may run less efficiently but it is normally still safe and can often keep working.

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

Regulates without flow temperature sensor (low loss header). Cause: short circuit, flow temperature sensor (low loss header)

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

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Related fault codes

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All 83 fault codes on the Vitodens 200-W B2HA-26

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

4C9A9b9C9E9F1018192830384044485051585990919293949899A3A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCFd6d7d8dAdbdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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