High Lockout
S.32 on Vaillant ecoMAX 618

Your boiler is pausing because its internal fan is not reaching the correct speed required to safely start the heating process.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Fan unit waiting period

What causes this fault?

This fault occurs when the boiler's control system detects that the fan is not spinning at the specific speed required to safely clear spent gases from the combustion chamber. The most common reasons are a build-up of debris within the fan motor or a communication failure between the main circuit board and the fan's power supply.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.32View →F.22View →

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