The oven makes a loud rattling sound when it reaches a certain heat (tends to be about 200 degrees) and then rattles intermittently until turned off. If you slam the door it does sometimes shut for a while. Doesn't appear to be the fan.

The fan needs be cleaned and lubricated. To do this: Turn off stove/oven. Remove fan cover plate. Remove fan. Clean and lubricate the shaft bearings with 3 way oil. Install fan and cover plate.

Since it is new contact the people that sold you the oven for warrenty repair.

The fan runs until it cools to a preset temp.

It sounds like the fan itself is bad. they can get loose and start to rattle or rub against the frame.

the fans wear out out and it sounds like your is on its way out you are better off replacing it soon before complete failer easy to replace your self if you need help let me know

It is most likeky that the fan bearing is worn and thus causing the rattling sound. You will probably need to replace the fan. Check first that there is no obstacle in the way of the fan rotating.

Replacement of the fan will require the back of the oven to be removed giving access to the fan unit, which will need to have the wires disconnected and the fan assembly unbolted. Fitting is the reverse.

Always remember to switch off the power before working on electrical equipment.

If the fan is working, but there is no heat in the oven at all, then it is going to be the element that is faulty, assuming it is an electric oven.
If the fan is rattling, then could be loose fan blade, or the bearings are failing.
Hope this helps.

Try to set it at 500 degrees and see if it goes off at 350. If it does, then it probably needs calibrating. You can calibrate it by taking the knob off and finding a set screw in the stem where the knob sits. If this is not the problem, you may have to replace the thermostat. By the way, check to see if your temperature probe is not touching the wall of the oven. It will give it a false reading. Let me know if any of these things work and we will go from there.

Hi

Check this link

http://repair2000.com/oven.html

sounds like it blew a fuse or the heating element burnt out on it,look to see if the element is burnt in two