This chart is based upon a specific gravity of 0.60 and 1,000 Btu per cubic foot for natural gas. My old gas manuals call for sizing to begin at the end, so let’s back our way out of the home’s lines.

1. ACE: “An appliance that operates with a nonpositive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.” a) Category I b) Category II c) ...

A catalog of the company’s gas vent products, L201, offers various items in the categories of gas vent systems, Dura/Connect® single- and double-wall connectors, and DuraFlex® relinings. Photographs, ...