Medium
51 on Ferroli Optima 201

Your boiler has sensed that the temperature inside the unit is too low and has triggered a safety mode to prevent the pipes from freezing.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Central heating frost thermostat

From this model's manual
Verified against the Ferroli Optimax 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.

DIY fix possible

Ensure the central heating system is switched on at the programmer.Carefully increase the room thermostat setting to encourage the boiler to fire up.If the boiler is in a very cold location like a garage, safely use a heater nearby to raise the ambient temperature around the unit.

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