Medium
48 on Viessmann Vitodens 200-W B2HA-19

The boiler has lost the signal from the temperature sensor that controls the water flow to one of your heating zones, so that zone may not heat properly, although the rest of your system should still work.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Mixer closes. Cause: lead break, flow temperature sensor, heating circuit 2 (with mixer)

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

47View →49View →

All 83 fault codes on the Vitodens 200-W B2HA-19

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

4C9A9b9C9E9F1018192028303840445051585990919293949899A3A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCFd6d7d8dAdbdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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