So there is a space on our furnace that is called a squirrel cage. I did some researching late at night because our furnace was making an bad thumping sound. I have deduced that the squirrel cage is the reason for our noise… The motor could sound almost care about it is bouncing if the squirrel cage bearings are out, however online said to put a sturdy piece of styrofoam under the cage to stop it from moving, however first, I did not care about that the service was not to actual service the system, however just adding something around the new home to stop it, but next, I did not care about that I had no idea what bearings or a squirrel cage was, and a squirrel cage is the type of fan that can be found in a furnace. It moves the air through the furnace plus this is what heats your home. The reason it has such a stupid name is that the fan looks care about a hamster cage. Apparently it is a lot of little fans definitely working together to move the air in plus out of the furnace, however most people just refer to it as a blower. The bearings or pieces holding it all together can prematurely wear out plus allow it to bounce around, how the bearings can wear out is the blower is unbalanced or the oil furnace has overheated to the point that the bearings could just not take it anymore… Either way, getting new bearings does not sound so costly. I would way rather do this than add foam under a piece in our furnace.