E03 displayed, flue gas safety device triggered

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Blocked chimney or flue, Reversed draft, Faulty flue gas thermostat, Poor ventilation in boiler room

Safety: Do not operate the boiler until the flue system has been checked. Risk of carbon monoxide.

1. Ventilation: Ensure boiler room ventilation openings are not blocked.
2. Flue inspection: Have the chimney and flue inspected and swept by a qualified professional.
3. Flue gas thermostat: Replace the flue gas thermostat if it is defective, but only after confirming the flue is safe.

Professional Required 5/5

Flue Gas Thermostat

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