My dad ran my truck with the Espar and never had a problem staying warm, even wayyyy up north in the Canadian winters. I rarely have it set over 2 o3 on the thermo. Way more expensive than a small heater, but wayyy less expensive that a APU.

BanditsCousin
.. just wondering what part of chi-town you in. I have lots of connections on the n/w side..

Down in the SW burbs (LaGrange, Palos, Darien) area