Navien CH-180 Installation Manual page 34

Venting:
Improper venting of combination Water Heater / Heating Boiler can result in excessive
levels of carbon monoxide which can result in severe personal injury or death. This
combination Water Heater / Heating Boiler must be vented in accordance with the
"Venting of Equipment" section of the latest edition of the ANSI Z223.1 / NFPA 54 Natu-
ral Fuel Gas Code and/or the "Venting systems and air supply for appliances" section
of the latest version of the CAN/CGA B149.1 Natural Gas and Propane Installation
Code in Canada and in accordance with all applicable local building codes.
This Navien Combination Water Heater / Heating Boiler can be vented with (PVC) plas-
tic. PVC Vent can be used in all cases up to Exhaust flue gas temperature 149°F(65°C).
IF you set the Water Heater / Heating Boiler at a temperature higher than 160°F (70°C)
AND are running an combination heating system, you MUST use plastic venting
(CPVC sch80) or any 3" venting system approved for use with Category IV appliances
(typically Type BH Special Gas Vent approved to UL1738-S636).
For best results, keep the vent system as short and straight as possible.
Locate the combination Water Heater / Heating Boiler as close as possible to the vent terminator.
The combination Water Heater / Heating Boiler vent must not be common vented with any other
gas appliance or vent stack.
Slope the vent toward the vent terminal at a rate of 1/4" per foot (2% slopes).
When slopping the vent using any other manufacturer's stainless steel vent, the assembly
of the vent pipe must be such that it is male-to-female in the direction of the flow of condensate.
The exhaust pipe and intake air pipe must be sealed air tight at each joint from exhaust pipe
to terminator.
Make sure that the seam of the vent pipe in horizontal runs toward the top of the
installation.
Note:
ings on adjacent homes, 45° elbows, 90° elbows or tees may be attached to the
end of the termination vent pipe to direct the exhaust plumes away from any
adjacent house as long as the total allowable vent lengths, maximum number of
elbows and distance to air intake restrictions are observed.
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To avoid moisture and frost build-up and to maintain clearances to open-