Low
S.46 on Vaillant ecoTEC plus System

Your boiler is temporarily limiting its power output to protect itself while it adjusts to the current demand from your heating system.

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

Protection mode: Minimum load

Engineer required

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

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Related fault codes

S.53View →

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