Medium
F.544 on Viessmann Vitodens 200-W B2HF System

Your boiler has detected an issue with the valve that regulates the temperature of your heating water, so it has shut that valve to protect your system while keeping the water pump running.

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. Heating circuit pump is operational.

From this model's manual
Verified against the Viessmann Vitodens 200 W B2hf System installation & service manual, page 102.
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

F.545View →F.546View →

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