Rinnai RH180 Installation Fundamentals page 29

Vent Guidelines: Exhaust
• This water heater must be vented/terminated vertically to the outside of the building or
structure. This water heater is NOT designed or certified for side wall horizontal vent
terminations.
• All installations must be vented in accordance with the National Fuel Gas Code NFPA 54/ANSI
Z223.1 – latest edition and the requirements of State or local codes. In Canada, the furnaces
must be vented in accordance with National Standard of Canada, CAN/CSA B149.2 – latest
editions and amendments and the codes of the local utility or other authority having
jurisdiction.
• NOTE: The vertical height of the Category I venting system must be at least as great as the
horizontal length of the venting system.
• All vent (Category I) passing through a concealed space, an attic or floor, MUST be Type B
double wall vent and/or Type B double wall vent connectors. For vent passing through an
internal wall, use Type B with ventilated thimble ONLY.
• The RH180 CANNOT be vented into any chimney serving an open fireplace or any other solid
fuel burning appliance.
• Use the same diameter Category I connector or vent as permitted by NFPA 54/ANSI z223.1
venting tables.
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