High
F.373 on Viessmann Vitodens 200-W B2HH-19

Your boiler has stopped because it is recalibrating its gas-burning settings and cannot complete the process, usually because it is not releasing heat into the water properly, which a reset and a quick check of the system can often clear.

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

Automatic calibration of the combustion controller: No. Ensure adequate heat transfer. Reset device.

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2hh B2kh 6219526 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

F.372View →F.374View →

All 12 fault codes on the Vitodens 200-W B2HH-19

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

A.11F.59F.62F.346F.357F.359F.369F.377F.380F.416F.457

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