Why does the cooling fan in oven run foerever?

A lot of electric fan ovens run the fan until the oven cools. This ventilated the cavity.

Cooling fan?
Surely the fan of a fan oven is there to circulate the heat within the oven to eliminate "cold" spots and shorten cooking times. Some ovens will allow the fan to switched off.

Probably the cooling fan. There is a cabinet thermostat on most ovens these days (Especially wall or underbench models) to keep the cooling fan running after the cooking has finished and oven turned off. This fan will run for a few minutes to cool down the outside of the oven so it doesn't burn / discolour the surrounding cabinet or workbench. If the fan stays on all the time, I would say that the thermostat has probably jammed in the run or on position.

The cutout stat for the cooling fan needs replacing

Chris Lindstrom,

I understand that you have a fan running while you are baking. This is a totally normal function of your applliance. A cooling fan may automatically turn on and off to cool internal parts. It is normal, and the fan may continue to run even after oven is turned off.

-Best Regards-

Is the background cooling fan running? Also, look under the oven and if possible take off the kick panel and clean all the rubbish out to ensure the cooling fan can circulate air round. As a check, when you turn any part of the oven on ( Main/top/grill) the cooling fan will run and you will feel a cool draft of air coming out of the gap just above the top of the main oven door. If the fan is not running, this will cause the unit to overheat and the overheat thermostats to kick in, turning the oven off.
If the fan is not running, you will have to take the whole unit out to gain access to the back panel.

Your oven has a fan to draw in cool air at the bottom of the front panel, pass it around the case, and then blow it out at a position towards the top of the oven. This is a completely different fan that is at the back of the oven itself.

The cooling fan is necessary as the materials in modern ovens are kept light and thin as possible to save weight and manufacturing costs, however the flipside of this is that if not cooled by the cooling fan, they would be damaged by the heat inside the oven itself.

The cooling fan will continue to run for some time after the oven is switched off, because it will wait until the oven has fully cooled down before stopping the cooling fan.

Self cleaning ovens usually use very hot temperatures. Therefore if your fan is designed to help your oven cool, it will run until your oven is cool. Leave it running until your oven is cool and it should stop. It it does not let me know.

The fan is in place to cool the electronics it will run after the unit is off it is possible you have a bad sensor on the fan circuit leaving it to run too long

3 to 4 hours is a long time. Get to the fans (behind the control panel) and check the screens for dust. Chances are the screens are clogged with dust and need to be cleaned so the fans can move air for cooling better. I had this problem on my GE JTP14, and after cleaning just one fan it can keep up with cooling the electronic area while the oven is running. It runs much less often.

Safety first! cut the breaker before removing anything with a nice conductive screwdriver! Hope this helps!