All computer fans starts ok but trips with notice,

There could be several reasons why a Petra package unit did not start after a fan was changed. Here are some possible causes:

Wiring issues: When changing the fan, it's possible that a wire was disconnected or connected improperly. This can prevent the unit from starting. Check the wiring connections to make sure they are secure and in the correct location.

Capacitor failure: The capacitor is an electrical component that helps the fan motor start and run. If the capacitor is faulty, the fan may not start. Check the capacitor with a multimeter to make sure it is within the acceptable range of values.

Motor failure: If the motor has failed, the fan will not start. Check the motor with a multimeter to see if it is receiving power and if it is within the acceptable range of values.

Thermostat issues: The thermostat may not be sending the correct signals to the unit to start up. Check the thermostat and make sure it is set to the correct temperature and mode of operation.

Circuit breaker tripped: Check the circuit breaker to make sure it hasn't tripped. If it has, reset it and see if the unit starts.

Control board failure: The control board is the brain of the unit and controls all of its functions. If the control board has failed, the unit may not start. Check the control board for any signs of damage or malfunction.

If none of these solutions solve the problem, it may be best to consult a certified technician who can diagnose and repair the issue.

Don't know this exact server. But my guess it is either a heat issue or a power supply issue. Turn it on with the cover off. Check the CPU fan(s). If your CPU is getting too hot the system might be shutting down power to save it. If everything seems cool it might be the power supply I have seen it when the power supply fan goes out on the power supply and the caps inside start to sizzle. Voltage ramps up and fail.
Hope this helps.
Also, Something that has tripped me in the past. Make sure the power button is not stuck. I had a server that the power button stuck down and it would turn itself off. Took me 2 CPU fans and a power supply to figure that out. LOL

Did you make sure that the element is not making contact with any metal after you put it in? That would cause whats happening in your situation.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/jason_4570d45317834dd3

If it is so loud that you notice it inside the car, it is about to fail.
Usually when these fail prematurely, it is because the check valve has failed, so the fan slowly spins backwards with hot wet exhaust gas blowing through it all the time you are driving. This destroys the fan bearing, resulting in the noise you hear and the subsequent fan failure. The fan costs $420 at the dealer or $240 on line. The check valve is $125 at the dealer or $105 on line.
There is a place on eBay that rebuilds secondary pumps for Volvos and BMWs for about half the cost of a new air pump. They did one for one of my 328s last year. It works fine, but I have not driven that car very much since I put it in.
Replacing the fan is an easy do-it-yourself job, but the soft rubber mounts that hold the fan are fragile, so don't abuse them or you will be making a second trip to the parts store.
You might want to disconnect the line from the check valve to the fan and start the car to see if the check valve is leaking before ordering a new one. Also, if there is water in the fan when you take it off the car, the check valve has failed.
If you just eliminate that fan, the car will run the same. It will just make a little more carbon monoxide when you first start it, it will take a bit longer for the computer to go into closed loop operating mode, and the computer will set a code for failed secondary air fan.
The gas consumption associated with this fan is negligible. It takes only a few drops of fuel to quickly heat and light off the catalyst. You will never notice the difference in mileage.

Sleep timer.

If you're referring to the fan on the CPU , and it does not run when you turn on the computer , yes replace it. The system is protecting the CPU from overheating . If you're not sure if the fan is bad , remove the computer access cover to the main board , then , turn the computer on and see if the CPU fan starts to spin. If you notice the fan blades vibrating or jiggling but not spinning , then replace the fan motor assembly .

Doesn't sound as though you have overheating issues.
With a 196 thermostat, a vehicle is designed to run at 200 to 210,and you were putting it under a load on your trip.
I don't know why you would think about changing anything,unless you were doing some trouble shooting, and a test you were performing, indicated a failed component.
I would change the thermostat, as preventative maintainance every five years, and watch for the fans to be working after a trip of five miles or so.
Your A/C may have been switched off, by the various computer systems, to prevent overheating, or it may be starting to have it's own issues.

I have a u1421 with the same problem! I notice the fan doesnt run too well, sometimes it doesnt run at all, needs a prod to get it running. I suspect with no fan, that the element gets far too hot, and then starts to leak to earth, tripping the RCD. I'm gonna try buying a new fan motor - you should ckeck if your fan is running full speed OK.

pop the CPU, take a closer look athe chip and the socket, make sure there is nothing can create a short of creating any kind of heat. if you don't find anything there, I suggest a new CPU in order.

It is probably a failed run capacitor for the compressor. Without the capacitor, the motor can't even try to run, but it will draw extreamly high amperage until it trips the thermal overload (avarage trip time 5-10sec) after it has a few second for the safety to cool off, it will try again. Either that or the compressor truly is seized