For the last month or so my furnace has been making a squealing noise, it sounds alot like a loose belt on a car. At first it was only making the noise when it started to blow air, but now it does it at intermittent times while it's blowing air, and every time it starts up. I thought maybe it was a loose belt, so I took off the front covers to have a look inside, and I can't find any belts. It looks like the hamster wheel is directly connected to a motor, but I can't see enough in there to figure out if it does use a belt or if it is directly connected. The Furnace is an older Lennox model, but it doesn't look to be more than 5-7 years old. The Central Air unit is only 4-5 years old, but I don't know if they replaced the furnace at the same time that they installed the Central Air.