Low
d.02 on Vaillant ecoTEC Plus 938

Your boiler is currently taking a mandatory rest period to prevent it from switching on and off too frequently, which is a normal protective feature.

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

Maximum burner anti-cycling time in heating mode: 2 to 60 min. Default: 20

Engineer required

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

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Related fault codes

d.01View →

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