Vent free gas heaters and hearth products are 99.9% fuel efficient and are the most flexible to install because no venting is required. This option is great when there is not access to a flue, chimney, or an outside wall. All vent free products have a tamper proof automatic shut down device (ODS) making them safe. They are available in many sizes and styles ranging from 5,000 to 40,000 BTU. In Virginia the maximum allowable size permitted in bedrooms is 10,000 BTU and 6,000 BTU in bathrooms. In North Carolina ; the maximum allowable BTU is 6,000. No vent free product currently may be installed in a bedroom. Other restrictions such as confined space may apply. Catalytic vent free models feature a catalytic combustor that further cleanses/scrubs air impurities. These units are considered premium models that utilize glass to funnel venting through its combustor.
B-Vent-Natural or Conventional Venting
B-vent allows connection to an existing flue or it can be installed vertically. Vent connectors are connected directly with the appliance's draft hood and an existing chimney or flue to carry the products of combustion outside. It is the best choice for replacing your current wood stove or for installations without a ready access to an outside wall. Higher efficient appliances may require a smaller flexible liner to be installed inside of the much larger masonry flue liner to promote proper drafting and prevent possible internal chimney damage. A characteristic of a B-vented appliance is that it uses inside air to support combustion.
Direct vent modes are considered to be the best choice in terms of indoor air quality and economy. These products draw outside air to support combustion. Inside air is warmed as it re-circulates around the sealed combustion chamber, and this warm air heats the room and reduces cold drafts. Direct vented units are ideal where existing chimneys and flues cannot be used as well as respiratory complications are a consideration (i.e., asthma, chronic allergies, pure oxygen is being used for medical therapy.