It is generally located behind the bumper on either side of the car (not in front of the radiator) in front of the inner fender. (mechanics.stackexchange.com)
Avoid exposing your furniture to excessive heat e.g. by placing it in front of a radiator, as this can cause cracking. (contentbyterenceconran.com)
Other (less involved) reasons include: a radiator fan that doesn't turn on when it should low coolant flow (e.g. failing water pump) debris inside or in front of the radiator Without knowing the specifics of your vehicle, you should see loss of... (mechanics.stackexchange.com)