High Lockout
E03 on Vokera Mynute Vhe

Your boiler has detected an issue with the system that vents exhaust gases safely outside, so it has stopped working as a safety precaution.

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

Flue gas thermostat or fan fault

What causes this fault?

This fault occurs when the boiler's safety sensors detect that the fan isn't moving air properly or the exhaust gases are getting too hot. The most common reasons are a blockage in the flue pipe, a failing fan motor, or a fault with the sensor that monitors the exhaust temperature.

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

E04View →

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