Fireplace Venting Options

Natural Vent

This type of fireplace venting uses economical B-vent pipe for a chimney.

• Uses room air for combustion and venting terminates above the roofline (like a furnace).
• More decorative, lower efficiencies.
• Zero clearance to combustibles.
• Relatively easy to install, space-saving depth, but requires finishing such as a mantel and surround.
• Large traditional fireplaces in clean-face or circulating models.
• Ideal for locating anywhere in the home where B-vent can be installed.
• Less Cost than Direct Vent

The Hearth, Patio & Barbecue Association recommends the installation of a carbon monoxide detector with all gas hearth products.

Vent-Free

A vent-free gas fireplace operates without a chimney, flue or vent, so you can install one just about anywhere. Therefore you don't need any fireplace venting for this type. Choose vent-free gas fireplaces, stoves, fireplace inserts and gas logs. Modern vent-free gas fireplaces:

• are inexpensive and have low operating costs
• are 99 percent energy efficient
  provide warmth during power outages
• are Design-Certified to the latest national safety standards (ANSI Z21.11.2)
• do not exceed 40,000 Btu/hr of heat output
• and are a source of pleasure for years to come.

• Eight million American homes and more than 45 million households worldwide already enjoy the comfort and convenience of vent-free gas fireplaces. In fact, more Americans are buying vent-free gas fireplaces than any other type of supplemental gas heating product. However, there are some areas where these units are restricted. Consumers must check with their local building departments before purchasing.

How they work
Vent-free fireplaces operate on natural or propane gas. Most models require no electricity. Natural or propane gas fuels the flame through a permanent line that is connected to a blue-flame/yellow-flame burner or ceramic plaque burner within the heating appliance.

Indoor air quality
The primary gas combustion byproducts that can affect indoor air quality are carbon monoxide, carbon dioxide, nitrogen dioxide, oxygen and water vapor (humidity). Today's vent-free fireplaces operate well within nationally recognized standards and recommendations for all five byproducts. American Gas Association Research Division confirms these low emission levels.

Oxygen Detection Safety-Pilot
Since 1980, vent-free gas heating appliances have been equipped with a unique safety-pilot system called an oxygen detection safety-pilot, or ODS. The ODS is the proven technological innovation that revolutionized the safety of vent-free gas heating appliances. The ODS automatically shuts off the gas supply in the rare event that the oxygen level in the room falls to 18 percent. Until recently, questions remained about the long-term effect of vent-free gas fireplace emissions on indoor air quality. In 1995, the Vent-Free Gas Products Alliance of the Gas Appliance Manufacturers Association (GAMA) commissioned a study on indoor air quality as it relates to vent-free gas heating products in the home. The results proved that vent-free gas heating products meet or exceed the most current and applicable nationally recognized standards and guidelines for indoor air quality. Even so, the Hearth, Patio & Barbecue Association recommends the installation of a carbon monoxide detector with all gas hearth products.

Source: gamanet.org

Direct Vent

Direct vent fireplace venting uses a coaxial pipe system (small pipe within a large pipe) and draws combustion air from the outside through the outer pipe.

• An inner pipe vents the exhaust.
• Can either vent out the top or out the back, for installation versatility.
• Can vent horizontally through an outside wall, or vertically through the roof - no chimney required!
• Ideal for adding warmth & efficient heating to a cold room.
• Most are certified as gas wall furnace for highest efficiency.
• Zero clearance to combustibles.
• Convenient to install, space-saving depth, but requires finishing such as a mantel and surround.
• Suitable for well-insulated homes or homes with no existing chimney.
• Always have an enclosed front.
• Best choice for newer, more air tight homes.

The Hearth, Patio & Barbecue Association recommends the installation of a carbon monoxide detector with all gas hearth products.