Interesting turn of events. The tech came to fix the heat pump and the first thing that he asked for was the manual. Turns out they don't install too many of these. So when he was thumbing through the manual he found that the guy from his company who installed it, installed it wrong. Instead of the unit sitting outside on the ground it is supposed to be raised off the ground 5 inches to allow the water to drain when it goes through it's defrost cycle.
Called the sales rep to yell at him and he made the mistake of telling me that he told my wife before we bought it that once it got to 20 degrees outside the unit wouldn't work. My wife is one smart cookie, smarter than me I would have to say -- and he never said that to her. I lived in Wisconsin for 37 years and I can tell you that it is below 20 degrees for most of the winter. Why in the heck would I install a unit that doesn't work when it gets cold outside. I think he started to squirm when I resent him an email from when we bought the unit and I questioned him if it would work in our shop and he said it would.
I think it's time to rip out the unit and get my $ back and have a different company come and install a furnace.
Here in central Texas heat pumps are very popular, and you are correct, they DON'T work when the temp gets below 30° (very rare here), and the heat pump units have an auxiliary electric heat strip that only comes on when either the temp is below the point at which the unit can squeeze heat from the cold air (about 35°), or it can be turned on for emergency heat if the compressor fails (has happened once in 16 years).
Heat pumps recover heat from the outside air, but when the temp drops below freezing, there is no heat to recover.
I heat 3200 s/f with two Lennox scroll heat pump/AC units (I'm in a rural location with no natural gas and Propane is very costly and a hassle to always have to fill the tanks), I am all electric. I keep the temp at 68° during the day, and cooler at night.
My last electric bill was $166 and because it has been very cold here the last few weeks, I expect the next bill to be near $200. Typically it will remain cold her thru February, last night it was 30°, today it's suppose to get to 50° and up to 61° tomorrow.
For us with only electricity, the Lennox Scroll heat pump is the most efficient source of heat, I do however use a small ceramic electric heater located in the printer room to keep the printer nice and cozy as I use a setback thermostat to drop the overall temp to 60° over night.
Here is a short video to show how a heat pump works:
http://www.youtube.com/watch?v=14MmsNPtn6U