Paul Rutherford

Hi, I was wondering if anybody has had this problem as soon as you start the car the fan is on I have changed the thermostat and also the water pump flushed the whole system though and this is still on, then when you start driving the hot temperature writing on the dash. All the radiator hoses are stone cold and this is after the car has been running. The car in question is a bmw 320d 2008 sport. Any help would be really helpful Thank you in advance