We moved to Vegas about a year ago and bought a two-story home with high vaulted ceilings. Both AC units were very old so we replaced them - thinking with newer technology we should be very comfortable.....but that didn't happen. The master bedroom would be freezing just to keep the rest of the upstairs at 80 degrees. We had several HVAC companies out to see what our options were but no real suggestions until Troy from Bishop Air Service came out. Not only did he find an improperly installed TXV with no insulation, he had several suggestions on how to help our situation. The life saver was a zoning system. This put our master bedroom, the kids bedrooms, and our large game room (all upstairs) on 3 separate zones with individual thermostat controls. It made a HUGE difference! Not only are we all comfortable but the AC comes on less. Troy was very knowledgeable and listened to our specific issues. Five stars is not enough!!