Sara Sage has done a bit of research on that for her house. Maybe she will see this, or message her using the site's built in messaging system (see the upper left hand margin titled messages.

When we sized the evaporative cooler for our modular, we left it up to the factory and their HVAC contractor (who is located in Provo near you). We ducted the unit just as a refrigerated air unit. I wish I could offer more information but I really don't know much about the details. Our house is 1450 sf and we placed four vents in the house. The unit itself will be placed outside in a location that has good air flow (not in a corner for example), preferably in a shady or cool spot and then connected to the venting system. I have misplaced the model no. of our unit so I don't even have that.

I don't know the particulars of your situation but it seems that you should try to find someone who is more enthusiastic and knowledgeable about installing the evaporative cooler. I wish I could be more help. We have yet to receive our modules so I haven't been able to look at the evaporative unit at all.

The local Breezair dealer should be more enthusiastic, partly because they are relatively expensive. Check the yellow pages for Breezair. Xcel energy in CO is offering a $200 rebate on swamp coolers.