Low temperature

Hi, I have a problem on my 2004 crd that I hardly ever get the engine up to operating temperature. It's probably not normal for the radiator fan to run immediately after starting, is it? I don't know what affects turning on the cooling. please advise what to look at. Thanks

Looks like the thermostat is stuck open...

The thermostats are designed to fail safe, so they stick open. The fan is always spinning but not always doing much, there is a thermostatic clutch that makes it work when the air flow heats up.
If you are in Europe there is a higher temperature thermostat available, not sure about America.
While you are at it it's worth changing the coolant if it hasn't been done recently, don't use anything except HOAT.