This September, we had a furnace installed to heat the basement. It's an Armstrong, two-speed, 95% efficiency unit. The specs say it can do 57,000 BTU/hr, and my basement is 1350 sq ft.

Yesterday was a cold day, so I had my first chance to try it out. The temp in the basement was 61 degrees. It took 4 hours for the furnace to heat it up to 71 degrees.

This doesn't seem right to me. I've never seen a furnace take this long. I called the furnace company, and they said the time doesn't matter, just so long as it can eventually get there and *hold* the 71 degrees. But that doesn't seem right either, because my furnace must be creating 57000 BTUs an hour as it's going full speed, which means I'm not efficiently heating my basement.

What do you guys think on this?