The blower in my Heatilator GNBC36 gas fireplace (installed around 2000) has become noisy and I want to do some maintenance. I tried to pull it away from the back wall of the lower area of the insert, but it's stuck tight. It seems like it's fastened in place, but I can't see any bolt, latch, or other type of connection. The blower is labeled EM3030LH-85. I can't find a manual or assistance after googling this info. Any ideas?