Lochinvar 3.5, 2.5 Vertical direct venting, Vent/air termination vertical, Determine location

3 Vertical direct venting

Vent/air termination – vertical

￿WARNING Follow instructions below when determining vent location to avoid possibility of severe

personal injury, death or substantial property damage.

Installation & Operation Manual

Figure 3-2Vertical Termination of Air and Vent w/Rain Cap

￿WARNING Do not connect any other appliance to the vent pipe or multiple boilers to a common

vent pipe except as noted in Section 2 on page 18. Failure to comply could result in severe personal injury, death, or substantial property damage.

NOTICE	Installation must comply with local
	requirements and with the National Fuel
	Gas Code, NFPA 54 / ANSI Z223.1 - latest
	edition for U.S. installations or CSA B149.1
	Installation Code for Canadian installations.

Determine location

VENT OUTLET

36" [914 MM] MINIMUM ABOVE AIR INLET

BIRD SCREEN [TYPICAL]

12" [305 MM] MINIMUM ABOVE ROOF / SNOW LINE

Locate the vent/air terminations using the following guidelines:

1.The total length of piping for vent or air must not exceed the limits given in the General Venting Section on page 17 of this manual.

2.The vent must terminate at least 3 feet above the highest place in which the vent penetrates the roof and at least 2 feet above any part of a building within 10 horizontal feet.

3.The air piping must terminate in a down-turned 180° return pipe no further than 2 feet (.6 m) from the center of the vent pipe. This placement avoids recirculation of flue products into the combustion air stream.

4.The vent piping must terminate in an up-turned coupling as shown in FIG. 3-1. The top of the coupling or the rain cap must be at least 36" (914 mm) above the air intake. The air inlet pipe and vent pipe can be located in any desired position on the roof, but must always be no further than 2 feet (.6 m) apart and with the vent termination at least 36" (914 mm) above the air intake.

￿WARNING Rooftop vent and air inlet terminations must terminate in the same pressure zone,

unless vertical vent sidewall air is set up as shown in the General Venting - Vertical Vent, Sidewall Air Section.

Figure 3-1Vertical Termination of Air and Vent

	BIRD SCREEN
	[TYPICAL]
VENT OUTLET	VENT
36" MINIMUM	12" [305 MM] MINIMUM
ABOVE AIR INLET
	ABOVE ROOF /
	SNOW LINE
	COMBUSTION AIR

5.Locate terminations so they are not likely to be damaged by foreign objects, such as stones or balls, or subject to buildup of leaves or sediment.

Prepare roof penetrations

1.Air pipe penetration:

a.Cut a hole for the air pipe. Size the air pipe hole as close as desired to the air pipe outside diameter.

2.Vent pipe penetration:

a.Cut a hole for the vent pipe. For either combustible or noncombustible construction, size the vent pipe hole per the vent manufacturer’s instructions.

b.Insert a galvanized metal thimble in the vent pipe hole (when required by local codes).

3.Space the air and vent holes to provide the minimum spacing shown in FIG. 3-1.

4.Follow all local codes for isolation of vent pipe when passing through floors, ceilings, and roofs.

5.Provide flashing and sealing boots sized for the vent pipe and air pipe.

Termination and fittings

1.Prepare the vent termination coupling and the air termination elbow (FIG. 3-1) by inserting bird screens. Bird screens should be obtained locally.

2.The air piping must terminate in a down-turned 180° return bend as shown in FIG. 3-1. Locate the air inlet pipe no further than 2 feet (.6 m) from the center of the vent pipe. This placement avoids recirculation of flue products into the combustion air stream.

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