Raypak 902B, 302B manual Support of Vent Stack, Vent Terminal Location, Combustion Air Supply

CAUTION: When condensate traps are installed, condensate must be routed to an appropriate container for neutralization before disposal, as required by local codes.

WARNING: Contact the manufacturer of the vent material if there is any question about the appliance categorization and suitability of a vent material for application on a Category III or IV vent system. Using improper venting materials can result in personal injury, death or property damage.

Support of Vent Stack

The weight of the vent stack or chimney must not rest on the heater vent connection. Support must be pro- vided in compliance with applicable codes. The vent should also be installed to maintain proper clearances from combustible materials.

Use insulated vent pipe spacers where the vent pass- es through combustible roofs and walls.

Vent Terminal Location

NOTE: During winter months check the vent cap and make sure no blockage occurs from build-up of snow or ice.

1.Condensate can freeze on the vent cap. Frozen condensate on the vent cap can result in a blocked flue condition.

2.Give special attention to the location of the vent termination to avoid possibility of property dam- age or personal injury.

3.Gases may form a white vapor plume in winter. The plume could obstruct a window view if the ter- mination is installed near windows.

4.Prevailing winds, in combination with below-freez- ing temperatures, can cause freezing of condensate and water/ice build-up on buildings, plants or roofs.

5.The bottom of the vent terminal and the air intake shall be located at least 12 in. above grade, includ- ing normal snow line.

6.Un-insulated single-wall metal vent pipe shall not be used outdoors in cold climates for venting gas- fired equipment.

7.Through-the-wall vents for Category II and IV appliances and non-categorized condensing appli- ances shall not terminate over public walkways or over an area where condensate or vapor could create a nuisance or hazard or could be detrimen- tal to the operation of regulators, relief valves, or other equipment. Where local experience indi- cates that condensate is a problem with Category I and III appliances, this provision shall also apply.

Combustion

Air Supply

Exhaust

Configuration

Heater Venting

Category

Certified Materials

Combustion Air

Inlet Material

	Vertical Natural	I	“B” Vent
From Inside Building	Draft Venting
(Non-Direct Venting)	Horizontal Through-	III	Stainless Steel
	the-Wall Venting		(Gas Tight)
	Vertical Natural	I	“B” Vent	Galvanized Steel
From Outside Building	Draft Venting				PVC
(Direct Venting)	Horizontal Through-	III	Stainless Steel		ABS
					CPVC
	the-Wall Venting		(Gas Tight)

Table M: Venting Category Requirements

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