2306.7.9.1.3 Piping.
FC § 2306.7.9.1.3
Piping in vapor-balance systems shall be in accordance with FC 5703.6 and 5704.2. Nonmetallic piping shall be installed in accordance with the manufacturer's installation instructions. Vapor return piping shall be installed in a manner that drains back to the tank, without sags or traps in which liquid can become trapped. If necessary, because of grade, condensate tanks are allowed in vapor return piping. Condensate tanks shall be designed and installed so that they can be drained without opening.
