Low
00:4 on Viessmann Vitodens 222-F

This code is not actually a fault, but a status indicator confirming your boiler is configured to control both your radiators and your hot water tank separately.

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

System design 4: 1 mixer circuit M2, with DHW heating

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