ok heres an odd one. i started a very small fire round 6:30 pm and at 8:30 the fan wasnt on but i presumed it was because the merrimack wasnt warm enough. i had the primary air control all the way to the right. i then took the lever and pull sharply to the left and then the fan came on. The top of the merrimack was a tiny bit warm and when the fan came on it blew warmish air. Usually for me to get the fan come on i have to have the top of the merri scorching. Is the primary air control actually what makes the the fan come on? i figured it was some sort of thermal switch? maybe the merri had to have several break in fires to sort the fan out? any ideas are welcomed.