Radiators hot all the time,Fault FC?

Radiators hot all the time,Fault FC?

Thermostat TR2, boiler:Worcester Bosch RD532i. Multifunction display shows fault FC,Text display shows Please wait.... initialising.....Radiators hot although heating turned down on thermostat. I use now Master switch to stop heating. Is it a problem with the Thermostat or textdisplay?

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