I bought a building that was burnt down and I completely remodeled it. I had an a/c guy put on a new Rheem/Rudd 3 ton 13 seer unit and install all new duct work and returns. I have 2 room that are not connected that the a/c cools/heats. In each room are 2- 12" round vents with 14" ducts and 2- 14"x14" return filter with 16" ducts in each room (remember the 2 rooms are not connected in any way) Now that summer is here and I am in Arizona, I keep the thermostat at 81 degrees, when it hits 105 degrees outside, the unit runs constantly and I watch the thermostat climb to 85 degrees. I thought maybe it was so hot out that, this is how its suppose to be. The other day I had a friend come by and look at everything and he said my filters (14" ducts in each room (remember the 2 rooms are not connected in any way) Now that summer is here and I am in Arizona, I keep the thermostat at 81 degrees, when it hits 105 degrees outside, the unit runs constantly and I watch the thermostat climb to 85 degrees. I thought maybe it was so hot out that, this is how its suppose to be. The other day I had a friend come by and look at everything and he said my filters (14") 1 in each room are way to small. Can anyone give me an idea if he is correct. Thank you very much, Mike