Footprint for 2-Ton Furnaces?

[Rhino1]

I have 4 80-year old gravity furnaces in a California basement (in California), which I'd like to replace.

I'm trying to figure out whether I can put 4 2-ton replacement furnaces (perhaps with coils for an a/c add-on later) in the same location, but I'm getting conflicting information.

I have about 42 available square feet in one end, and 29 available square feet in the other. In the middle are water heaters and a washer/dryer.

Is that likely to be sufficient space?

Thank you in advance.

 

[Dana]

Does anybody even make replacement gravity furnaces anymore?

Or are you looking at using the same ductwork for an air-handler driven solution? (Not the best idea with the grossly oversized and perhaps not well balanced ductwork.)

How sure are you of the loads? Most houses/condos/apartments in CA can be heated with a condensing water heater feeding a hydronic air handler, and it could be 2 tons, but could also be a lot smaller.

The smartest thing to do would be to find a competent third party such as a RESNET rater or certified professional engineer to run an aggressive room by room, zone by zone Manual-J load calculation, which would allow you to make intelligent choices on the equipment.

A heat pump rather than a furnace might also be the "right" solution, depending on where the load numbers come out. A 0.75- 1.5 ton mini-ducted mini-split heat pump such as Fujitsu's 18RLFCD takes up less than 10 square feet of floor area if mounted vertically, or none at all if mounted below the ceiling in a closet or soffit, best mounted in the space they are heating (to keep the duct runs short and non-lossy) rather than in a basement.

This 1.5 tonner is heating & cooling a 1200 square foot single story house in Berkeley, installed as part of a major renovation, but there are other ways to mount them:

 

[Sponsor]

 

[Rhino1]

Thanks for the suggestions!