High
F56 on Ferroli Bluehelix Pro RRT

Your boiler is struggling to detect the flame needed to heat your water and home, likely because the sensor that monitors the burn is worn out or out of place.

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

Electrode damaged or not correctly positioned.

From this model's manual
Verified against the Ferroli Bluehelix Pro Rrt installation & service manual, page 40.
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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