Actually these are quite common. Trane, Carrier, DayNight and several others make residential gas furnaces of 90% efficiency or higher. Usually they are sealed combustion units and require a condensate drain. They all come with cooling options but that cycle efficiency is of course, usually stated in EER or SEER.
I believe mt31 is talking about a packaged unit, as opposed to a furnace with split system AC.
Split systems are very versitile, and you can easily match a high efficiency AC and furnace. But in packaged units, I have only seen standard efficiency (80% AFUE) gas heat, even with high SEER (16+) cooling. Maybe someone can tell us why.
Yes KENRAD, thats right. I have dealt with 90% split systems for residential applications. I have not been able to offer lght commercial pack units with the higher eff. on the heating side of the system. I can imagine that there are some obstacles to this. I would like to be able to put high eff. heating in light commercial, this is a high energy consumer and we should address this for conservation of energy. I still researching this myself. thanks
