NEW FURNACE replacement and/or installation after 5/1/2013 will require a 90%+ AFUE Gas Furnace. This means that all new residential furnace applications in Minnetonka, Minnesota will require PVC venting to the outdoors.
A true benefit if your furnace is a sealed combustion type unit. Eliminating your old gas furnace from possible back drafting within your home. Most importantly, reducing possible carbon monoxide poisoning through any draft opening and/or open burner type system. The enclosure of the burner compartment is sealed from the home for burner combustion. With two-pipe, direct vent type systems, combustion air intake/exhaust comes directly from outdoors.
90%+ efficiency natural gas furnaces are condensing units, on average, when operating, draining up to 5 gallons of water on a cold winter day. Two pipe vent (direct vent) dedicated to outdoors are highly recommended. An operable floor drain or water drain outlet is highly recommended for proper condensate removal when in operation. If no floor drain is accessible, a water (condensate) pump w/safety switch will be required.
There is no need to apply additional combustion air as required in many states for furnace only operation. Other gas appliances may require combustion air within your home. There is no further need for a "chimney" for venting purposes such as with any 80% AFUE type furnaces. Therefore, minimizing any rust, corrosion and maintenance of vent pipe including downdraft problems within your existing chimney.
In conclusion, on average, for every heating dollar spent, .90 cents will be spent heating your home. Many furnace manufacturers also provide additional energy savings with an energy efficient ECM or Variable Speed Blower Fan Motor. Savings upward of 70% on your furnace fan blower operation. On average, the cost of operating a 100w light bulb annually. 2013 Best Buy.