Low
00:4 on Viessmann Vitodens 333

Your boiler's internal settings are currently configured to manage your home heating zones and hot water separately, which is a normal state for this model rather than a sign of a mechanical failure.

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.

Technical description

System design 2, 5: 1 mixer circuit M2, with DHW heating

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

00:2View →

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