[kristiereed]

We are thinking about getting a central air system for our home. The home is 3500 sq. ft. two story. Although 3 bedrooms and 3 other rooms are shut off, (doors and vents closed). Our Lennox furnace was purchased just last winter. How big of a unit would we need to just be comfortable, (don't need to be freezing). Plenty of large shade trees around the house. We live in southern Ohio so summers can be very hot and humid.
Thanks

[hvac1000]

We are thinking about gettin a central air system for our home. The home is 3500 sq. ft. two story. Although 3 bedrooms and 3 other rooms are shut off, (doors and vents closed). Our Lennox furnace was purchased just last winter. How big of a unit would we need to just be comfortable, (don't need to be freezing). Plenty of large shade trees around the house. We live in southern ohio so summers can be very hot and humid.
Thanks

Sorry but a lot more info will be needed to properly size your unit. This is not guess work. You will have to have a Manual J done for your entire home. While you might be able to do that I highly suggest you contact a true ON SITE professional from your area to undertake this time intensive task. By doing a proper manual J you will be sure of enough cooling and spare yourself from all the problems associated with to large a unit.

Go to Google and type in Manual J to search for more info. In the mean time the little attachment might be of interest and knowledge.