Rinnai RH180 Installation Fundamentals page 30

Vent Guidelines: Exhaust
• It is not permitted to reduce vent diameter (4").
• Vent or vent connector runs should be as short and
direct as possible.
• Vertical outdoor runs of Type B or ANY single wall vent
below the roof line are NOT permitted.
• All horizontal vent runs to be sloped up away from the
RH180 a minimum of ¼" (6mm) per foot.
• All horizontal vent runs are to be supported, at a
minimum, every 6 ft. (2 m) using suitable clamps and/or metal straps.
• Existing exhaust vent or chimney is to be checked to ensure they meet clearances and local
codes.
• The RH180 can ONLY be connected to a manufactured chimney or vent that complies with a
recognized standard. Venting into a masonry or concrete chimney is only permitted as outlined in
the NFPA54/ANSI Z223.1 National Fuel Gas Code venting tables. It is therefore a contractual
obligation on the part of the installer to follow all safe venting requirements.
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