Heating and cooling. Cooling and heating. It has been a holiday season that has tested the limits of many a HVAC design. From every corner of the country, the temperature extremes of this holiday season are making their way into the record books. From Christmas morning thunderstorms with lightening bright enough to wake the kids, to early afternoon double rainbows, some parts of the country experienced record temperatures and unusual weather events. Every home owner, however, whether in South Dakota or Texas and dealing with record setting lows or in places with high temperatures that delivered rain instead of snow…