Low
P03 on Ferroli Leb TS

Your boiler is temporarily pausing because the underfloor heating water has become slightly too hot, and it is now waiting for the system to cool down before starting up again.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

The underfloor heating temperature drop that lets the boiler restart after shut off when the supply became higher than the set point

From this model's manual
Verified against the Ferroli Leb Ts installation & service manual, page 8.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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