Good point beenthere, I didn't notice his 73º indoor design temp.
While I would never ever advocate such a low indoor design temp, if someone does insist on it, you MUST look at the performance of the equipment at those indoor and outdoor conditions. Using the ARI rated capacities will result in a system that will not do what you are wanting.
Many manufacturers don't even make the performance data available for thier equipment at conditions other than ARI conditions.
This is sounding more and more like a good application for a 5 ton outdoor unit with a smaller indoor unit.
A Trane 5 ton XR13 heat pump with a TWE049E air handler running 1800 CFM gives 51500 btuh total and 43,400 btuh sensable capacity at his design conditions. At those design conditions, thats a LOT of extra latent capacity for humidity control, wich is very desireable in humid areas.
[Edited by mark beiser on 08-05-2006 at 09:07 PM]