Can I Install My New Gas Furnace in My Attic?

Yes, attic installation is usually allowed

A gas furnace can normally be installed in an attic, subject to your local code requirements. Every furnace sold by AC Direct is compatible with horizontal installations and is approved by the manufacturers for use in attics. Horizontal mounting lets the unit lie on its side and move air through ductwork that runs across the attic floor, which is a common layout in warmer climates and slab homes that have no basement.

The freezing concern with high efficiency furnaces

High efficiency condensing furnaces, rated 90 percent AFUE and above, produce liquid condensate as part of their operation. That water exits through a condensate drain line. If the ambient air in the attic drops below freezing, the condensate can freeze and create a blockage, which stops the furnace from running correctly.

For condensing type furnaces, there must be at least enough heat in the attic to keep the temperature above freezing. This limitation does not exist for standard efficiency furnaces rated at 80 percent, since they do not produce condensate that needs to drain.

Quick comparison by efficiency

Confirm your local code first

Local building codes set the final word on attic furnace placement, clearances, platform support, and required service access. Check with your local authority or a licensed installer before you buy, so the unit you choose matches what is permitted in your area. AC Direct ships the equipment, and you keep the AC Direct Price Promise on your purchase.