Low
738 on Viessmann Vitodens 100-W B1GA

Your boiler is connected to a smart heating control that hasn't been set up correctly in the system settings yet, so it is just waiting for the right instructions.

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

Normal operation OpenTherm remote control connected but not configured

From this model's manual
Verified against the Viessmann Vitodens 100 W B1ga installation & service manual, page 66.
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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