Burnham FREEDOM Installation, Operating And Service Instructions page 19

9) Pitch of Horizontal Piping - Pitch all horizontal piping so that any condensate which forms in the piping will run towards
the boiler:
• Pitch U.S. Boiler horizontal concentric venting 5/8" per foot
• Pitch Stainless steel venting 1/4" per foot.
10) Supporting Pipe - Vertical and horizontal sections of pipe must be properly supported:
• Support U.S. Boiler concentric venting near the female end of each straight section of pipe.
Exception: Vertical runs of concentric pipe in an unused chimney (Figure 7.36) need only be supported at the terminal
and at the base of the run.
• Support stainless steel venting as called for by the vent manufacturer's instructions.
Figure 7.7: Snorkel Terminal Configuration
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