Raypak 1501 - Manual (Page 34)

SECTION J-2 Horizontal Thru-Wall Venting Without Add-on Condensing
Heat Exchanger (Category III)
Figure J-2
HORIZONTAL THRU-WALL VENTING WITHOUT ADD-ON
CONDENSING HEAT EXCHANGER (CATEGORY III)
• Horizontal Thru-wall Direct Venting System (Category III) Installation
These installations utilize the boiler-mounted blower to vent the combustion products to the outdoors. Combustion air is
taken from inside the room and the vent is installed horizontally through the wall to the outdoors. Adequate combustion
and ventilation air must be supplied to the boiler room in accordance with the National Fuel Gas Code or, in Canada, the
latest edition of CAN/CGA-B149.1 and .2 Installation Code for Gas Burning Appliances and Equipment.
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