I was just sent to a resturant because the breaker was tripping on the exhaust fan circuit. There are 2 fans on the same circuit. The feed is a 12 wire, but the neutral is shared with another circuit. The 2 fans draw 8.9 amps when running, but after a few minutes the breaker trips. The breaker will not trip if the fan on the left is running by itself. As soon as the fan on the right is turned on it trips a few minutes later. Here is the kicker. We just replaced the fan on the right, and it still does the same thing! New breaker also. Any Ideas???? Thanks