Medium
308 557 on Ideal Mexico Super CF3 40-80

Your boiler is likely having trouble reading the temperature setting because the control knob is faulty or incorrectly positioned.

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

Thermostat knob

From this model's manual
Verified against the Ideal Mexico Super Cf3 40 80 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

Carefully turn the thermostat knob back and forth several times to clear any dust from the internal sensor.Ensure the knob is firmly pushed onto its spindle and not loose.Set the dial to your desired temperature and check if the boiler fires up.

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