High
F37 on Ferroli Leb TS

Your boiler has stopped working because the water pressure inside the system is too low to operate safely.

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

The water pressure inside the installation is not correct (pressure too low, water pressure switch not connected or defective)

From this model's manual
Verified against the Ferroli Leb Ts installation & service manual, page 7.
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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