2001 St. Croix Afton Bay. Since end of last season smoke pours out of 2 holes on bottom of stove at front corners after it ignites. Fan was sounding anemic. Evaluating today. Had to suck smoke out with shop vac outside to keep it from filling the house until pellets in burn pot all burned up. Even though the stove was hot, exhaust fan turned off when I turned the stove off. 15 minutes later, with stove off, exhaust fan suddenly came on and sounded strong. Now everything is working fine. Do I need a new fan, thermostat, control panel…? Pull the fan an clean it?