Profile: Wisconsin Fuel & Heating, Inc. markets heating & air conditioning services. Bryant plus 90 (Model 350) is a natural gas furnace that keeps the home warm and comfortable with up to 95.5% AFUE. Our Plus 90 allows relaxing in quiet comfort without distracting furnace noises. We also produce Bryant's exclusive stainless steel combustion chamber, which is an oil furnace that acts as a heat exchanger to help the furnace convert oil to heat quickly and responsively.