Have had a Breckwell Big E for a year and a half. Has been very reliable thus far but recently the room air blower shuts off. I thought it was a high heat sensor but, it only shuts off when running on the # 4 setting and will shut off any where from 20 - 40 minutes after start. The weird thing is when it shuts off, the convection fan, auger, and combustion fan still works. I even went outside to check to see if exhaust was still coming out of the vent. How can the room air blower stop, and the combustion blower still work, arent they the same motor? The blower will come back on after about 15 minutes. Any thoughts?