Raypak 751 manual Model

Model	Venting Category	Certified Venting	Vent Size (inches)	Maximum Vent
		Material		Length (feet)
		UL 1738 Certified		55 Subtract 10 ft per
		Venting Material e.g.
ADB-751 w/CHX	IV		8	elbow, Max. 3
		AL29-4C Stainless
				elbows
		Steel PVC*, CPVC*
		UL 1738 Certified		55 Subtract 10 ft per
		Venting Material e.g.
ADB-1001 w/CHX	IV		10	elbow, Max. 3
		AL29-4C Stainless
				elbows
		Steel PVC*, CPVC*
		UL 1738 Certified		55 Subtract 10 ft per
		Venting Material e.g.
ADB-1501 w/CHX	IV		12	elbow, Max. 3
		AL29-4C Stainless
				elbows
		Steel PVC*, CPVC*
*Contact the manufacturer for details.
Table O: Vertical Vent (CATEGORY IV) with Add-on Condensing Heat Exchanger

Vertical Vent (Category IV) with Add-on Condensing Heat Exchanger 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 vertically through the roof to the out- doors. 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 edi- tion of CSA B149 Installation Code for Gas Burning Appliances and Equipment.

UL 1738 Certified Venting Material (e.g. AL29-4C) MUST be used. The vent must be installed to prevent the flue gas leakage. Care must be taken during assembly to ensure that all joints are sealed properly and are airtight.

For certain installations, i.e. pool, heat-pump domestic hot water with pre-heat tank, PVC or CPVC may be used. Contact the manufacturer for details.

To prevent the condensation accumulation in the vent, it is required to install the horizontal portion of vent with a slight upward slope of not more than 1/4" per foot of horizontal run and an approved condensate trap must be installed per applicable codes.

WARNING: No substitutions of flue pipe or vent cap material are allowed. Such substitutions would jeopardize the safety and health of inhabitants.

The Stainless Steel non-restricted direct vent cap must be furnished by the boiler manufacturer in accordance with its listing.

Fig. 26: Horizontal Thru-wall Venting with Add-on Condensing Heat Exchanger (CHX)

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