So....I'm impressed. Yesterday was very cold, and nighttime dipped to ~ -6*F. With four loads, was able to keep our 2000sqft downstairs at 75*, and the 1000sqft upstairs at 62*. It doesn't get much colder here (although tonight is supposed to reach -16*), so......I'm very happy that the Mansfield appears able to handle what New Hampshire winters have to offer - have been waiting for the brutal cold to see if she could hold her own - passed with flying colors! Cheers!