Emergency
S.56 on Vaillant ecoTEC exclusive

Your boiler has detected high levels of carbon monoxide and has automatically paused operation to keep you safe while it waits for the fumes to clear.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Waitingtime:COlimitvalueexceedance | Waitingperiod:COlimitvalueexceedance

Engineer required

This is a emergency 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.28View →F.29View →

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