The furnace makes loud blowing sounds when it comes on for several minutes. How can I correct that loud noise?

The loud blowing noise can be a sign of either the furnace moving too much air all at once or that the ductwork isn't properly sized for its application. Fortunately, this furnace has a multi-speed blower that is capable of operating at different speeds. Adjusting this blower speed to a slower setting should be able to reduce the noise. If this does not work, please call in and ask for tech support. They will gladly help remedy your problem.