Low
d.2 on Vaillant ecoMAX System 612

Your boiler is currently in a forced waiting period to prevent it from cycling on and off too frequently, which is usually a normal part of its operation.

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 system max. off-period

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.1View →

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