We had a high-efficiency furnace installed, replacing a 30-year-old mid-efficiency furnace, in August. The installation itself took two full days, during which the installers knocked a two square foot hole in our foundation (that they didn't even attempt to fill) and made a disaster area our of our basement (that they didn't even try to clean up). When they said they were done, they turned on the heat and it ran for 30 seconds or so before none of us could stand it any longer. Worked the first time.
Second time, not so much. We turned it on once the weather started to get colder (day before Thanksgiving) and found that it wouldn't come on. We called and called and called for a week before they sent someone out to see what the problem was. Turned out to be the installer again. He managed to figure out that the igniter wasn't igniting the gas. He took the part and left, saying he would get the new part.
From the sounds of things, he took the part, dropped it on somebody's desk up at Aire One and didn't leave much of a note. Another day later, now our fifth day without heat, we started calling again, trying to find out what the hell is going on. Turned out they didn't have any igniters in stock (a furnace company?) and that the had to order it.
The following Friday, after a week without heat, we finally had a tech come and install the new igniter. Heat was back on. Perfect.
As the weather crept down below zero, we found that the heat would sometimes work, sometimes not. And that there was a real gurgling noise coming out of the pipes outside.
Turns out that the pipes were not installed at enough of an angle for them to drain properly,and now there was enough water in them to block the pipe entirely. Then, as the water dipped below freezing, it would block the pipe completely.
So, no heat again. Plus a hole in the foundation that you could shove a small child though, that I had to fill myself.
They've sent out the installer to have a look at it again and I'll update this review depending on the result.