I see now, they are using the 30psi for the sprinkler heads as a "loss". Anyway, I would not combine the two bigger zones, thats approx. 15 gpm through 3/4" copper service. Max we would go under right conditions is 11-12 gpm. You may get premature meter failure. You could do the 7.4 and 1.56 together. (how did you get 1.56 gpm ). 15 gpm through 3/4 K copper loses approx. 30psi/100 ft. at approx. 11 ft/sec Too high ! Stay with 2-3 zones. How long is your service line. 3 psi loss seems low for that item based on your flows.

carterinms, I must thank you again. I remember now seeing something on the FEMA website right afte Ike and we were doing all of our mitigation research. So many websites I have visted for sure. Many of the homes destroyed during Ike were older and in High Velocity zones and from what I hear it didn't matter what type foundation they had, becuase the surge was just so high and the debris field was so broad, that they didn't stand a chance. The ones that were left standing, whether wood or concrete, were the new construction that were at 18'-20' elevation above grade. We aren't high velocity, although after Ike, I don't think I can ever be too sure what may happen. We are a 1/4 mile from the bay and never dreamed we'd get that much water up here! Have you all gotten to move in yet? I hope so, it certainly was a long time coming. We haven't broke ground yet, but we are closer. Many of our neghbors are back in their homes, so the neighborhood appears to be coming back, which is a blessing. Anyway, I do thank you again. Would you mind posting the link to the journal on your build? I thought I had it in my favorites, but I don't and I can't find my other post. Best Wishes!

Bob, I just went too a class on this high velocity system. The ducts are obviously only 2 inches in diameter, there like a hard flex and do not collapse easy. in other words if they where in the back of a closet you really don't have to box them in at all. There made from the same material as an exhaust from the old Volkswagen. From what the instructor said it has a bigger surface for removing cooing so it actually has a high seer rating also. I forget the total amount of registers for tonnage but it is all written down for you. I think but I mass not sure but the 2 inch flex duct can go up to 40 feet. It is great in new fancy homes where there are no wall walls and has glass everywhere in the house. if done right the noise level is low and not noticeable and more humidity is removed out of the air. In other words if it is 100 out and you cool your house to 80, which is a 20-degree difference, you will feel cooler. It is on the expensive side but trouble shooting is the same way as a conventional air handler. It even has a spot for a heat exchanger to go into the air handler for heat. If ducts or disturb. Is a problem, this is an excellent choice. Now finding someone that can do it is another problem. Ps. I know I am going to get grief you guys love bashing me. by the way I put in a water heater for some chick and I took 75 off for topless and handing me tools. I used the propress tool so I did not have to use a torch at all.

Refrigerant level could be low. When was the last time the system was serviced?