Low
d3:14 on Viessmann Vitodens 333

This code is not a fault; it is simply a display setting confirming your boiler's current programming for how much it increases water temperature based on the outdoor weather.

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

Heating curve slope = 1.4

Engineer required

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

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