New Furnace & Plenum Install Question

rb404

Description:
I recently removed an old (25 yrs) gas up-flow single stage furnace. The furnace sat on a very firm plenum base with a side opening return and this base raised the unit about 24 inches from the ground. There was an evaporator coil mounted in the standard top of furnace position. The plenum base set-up seem to be moderately lacking some efficiency and filtering in its design.

Question:
Will it make much of a difference if I install the new furnace on the floor and place a 24 inch plenum to connect the evaporator coil to the new furnaces heat exchanger top opening? I am basically eliminating the old furnace base type install and substituting a plenum on top to make up the distance. I am not in a position to move the coil and I really did not want to go back to the plenum base design.

Suggestions / Opinions please...

hvac5646

I would normally say yes as long as the bottom is not connected into the cold air return.

Knowing size of home and and a pic of the furnace would help a lot.

Marty S.

Is the furnace in a garage? If so the furnace has to be kept raised off the floor.

rb404

The home is about 1200-1500 sq ft. The furnace location is a hall closet and it will be similar to this type of standard model. http://www.alpinehomeair.com/partner...1204_640_0.jpg I suppose I could sit the furnace on the plenum I have. It was custom done buy a company here in Atlanta but the weight of a furnace seems a bit much to me for it's design. I would much rather sit the lighter coil assembly on top.