I have a Lennox ML180. It was installed about 6 months ago. Ever since it was installed the blower motor has always been noisy and can be heard through all the vents in the house. The blower motor is loud and it sounds like a humming noise and is unpleasant to listen to when the heating or air condition comes on. The furnace has always sounded this way since it's been installed. I wonder if anything can be done to fix this. Most furnaces that I have heard have a blower motor that runs and you just hear the air moving, not an annoying hum. It almost sounds like a big hair dryer running through all the vents in the house. If anybody else has a Lennox ML180 let me know if you experience the same noise.