Two stages for two AC units?

re8

Friend is installing two AC units into a home in suburban Philadelphia (one zone for each floor). The question is whether it makes sense to put two-stage units (like the Lennox XC21) - would this help keep things "in balance"?

don_9

It depends

Depending on his shr,.lots of time contractor will installed two zone bc it the way it has always been done and we all have different opinion why we do it.

I find often times you can get by with one system with a zone damper system which should get you very close to meeting your sensible heat load with one system verse two,With two system it hard keep from being oversize and.lets not forget adding 20% to upstairs unit bc hot air rises and cool air falls. Now you have a unit upstairs that run time all the time in the summer while the down stairs unit run in short cycle mode..

So being that may be the case having longer run time that you will get with two stage equipment will help with the oversizing with two units.Longer run time will help with temp swing and also help dehumidify alittle better over a single stage unit.





 

re8

Thanks

That was basically what I was thinking. The two zones are there in part to avoid running the ducts through the 2nd floor closets - space is very scarce:-)

re8

Thx