Fireplaces That Do Not Require Outside Venting

Vent Free Fireplace Designs

• Vent-free fireplaces are designed to fit any decor, from traditional to contemporary. The units may be placed anywhere as they are not restricted by the need for a chimney or a vent to the outside. In homes where space is at a premium, ventless fireplaces as slim as 8 inches deep can be hung on any flat wall with no framing or special construction required. Other models provide a corner or two-sided fire box to be enjoyed from various areas in an open concept living space. For the traditionalist, a vent-free firebox placed in a brick-lined interior houses a log set that never requires maintenance or replenishing.

Air Quality Issues

• The combustion of natural gas or propane gas produces carbon monoxide, carbon dioxide, nitrogen dioxide, oxygen and water vapor. The research division of the American Gas Association has confirmed that the vent-free fireplace products, bearing the AGA seal of certification, operate well within the national standards and recommendations concerning the emission of these combustion by-products into the inside air of a dwelling. Heat input of the certified units do not exceed 40,000 British Thermal Unit per hour (btu/hr) of heat output, thereby conforming to national safety standard ANSI Z21.11.2.

Safety Features

• Since 1980, vent-free gas heating appliances have been equipped with a safety pilot system called an Oxygen Detection Safety pilot or ODS. If the oxygen level in a room, normally at a level in excess of 20.9 percent, falls to 18 percent thereby allowing the carbon monoxide level to drastically increase, the ODS automatically shuts off the gas supply and combustion ceases. In 1995, the Vent-Free Gas Products Alliance of the Gas Manufacturers Association--now the Air Conditioning, Heating and Refrigeration Institute--commissioned a study on vent-free gas heating products in the home. The results of the study proved that the vent-free products met or exceeded the standards for interior air quality.