Q: The problem we have is our a/c condensing coil freezes up, causing the house to not cool properly. It seems to be happen during the late afternoon/evening, when the temperatures get warmer and it gets more humid outside, which causes the system has to run more. Since the installing company has been unable to determine what is causing the a/c to freeze up, we are now wondering if the system that was installed is sufficient for the size of our home.

We do not believe capacity is the problem for the system freezing up. A freeze up is generally due to loss of refrigerant or lack of airflow. You may not have a leak in the coil, maybe a leak in the refrigerant lines in the wall. When the siding was replaced they may have nicked the copper. A good leak tester should be able to locate a refrigerant leak.

You may also have issues with the comfort and not having the airflow settings correct. Have the contractor leak test the system and Freon lines to check for any leaks. Also have them check the airflow settings.