I have a 2,000 s.f. bi-level home and our lower level is always about 5-10 degrees colder than the upper level. We have a gas forced hot air system and it is 1 zone for the whole house. I have tried closing off some vents to help improve the temperature down stairs but that has not worked. I am not sure what we can do to improve this siutation. Are furnace is located in our laundry room which is down stairs. Any insight would be great.