High
Alarm on Firebird Envirogreen

Your boiler has detected that there is not enough water flowing through the system to operate safely, so it has shut down to protect itself.

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.

What the manual says

Manufacturer manual

If the water flow is under 12 litres / minute (6 litres / minute for 7.5kW unit) (with flow switch tolerance), alarm will be displayed on the unit.

From this model's manual
Verified against the Firebird Envirogreen installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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