Low
S.95 on Viessmann Vitodens 222-F B2TF

Your boiler is working fine, but it is currently waiting for a signal from the third heating zone's thermostat before it starts heating that area.

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

No demand; external hook-up, heating circuit 3

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf 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.

DIY fix possible

Check the thermostat or programmer for Heating Circuit 3Ensure the target temperature on that thermostat is turned up higher than the current room temperatureCheck if the batteries in your wireless thermostat need replacing

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Related fault codes

S.92View →S.93View →F.95View →

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