Two manufacturers of plastic venting systems are pushing for a national fuel gas code in the United States that requires Underwriters Laboratories Inc. certification for use in some natural gas-fired ...

We had a new high efficiency gas furnace installed in our house about a year ago. The contractor informed us that the new “code” required that the furnace be vented out the side of the house instead ...

The High-Efficiency Direct-Vent Furnaces are available in three models: 7,400-29,400 Btuh. The furnaces, model series 07735, 17735, and 29035, are designed as high-efficiency, low-profile furnaces ...