Low Information
72:0 on Viessmann Vitodens 333-F

Your boiler is notifying you that the hot water circulation pump is currently active based on its set schedule, though it may indicate a minor communication lag with the sensor.

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

DHW circulation pump: ON according to time program

What causes this fault?

This code appears when the boiler’s internal control unit recognizes that the secondary hot water pump is running as per its scheduled timer. It is typically a status notification rather than a breakdown, though it can sometimes be triggered by a slight delay in the electrical signal between the pump and the main circuit board. You will usually find your hot water is working perfectly while this code is displayed.

DIY fix possible

Check your hot water time program settings to ensure the 'On' period is intentionalTurn the boiler off at the main isolation switch for 30 seconds and restart itMonitor the display to see if the code clears once the scheduled period ends

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