Their heat pump was just installed last year, near the end of the cooling season. The installing contractor was rushed for time, but the new, 2.5-ton, R-410A unit (plus indoor coil) was installed, charged, and operating quickly.

At the start of the 2006 cooling season, Kelly switched the thermostat over to cooling, and it works, but the fan always seems to be running. As the outdoor temperatures get hotter, the unit seems to run nonstop. Eventually it runs all day long and the 1,600-square-feet house doesn't cool down.