American Water Heater 318935-003 Vent Pipe System, Draft Hood Installation, Vent Pipe Size, Legs

	Alternative
	Opening
	Location
Confined	1 sq. Inch
Space	Per 3000 BTU/HR

Figure 8B

All Air from Outdoors

Using a Single Permanent Opening

Vent Pipe System

This water heater uses a non-direct, single-pipe vent system to remove exhaust gases created by the burning of fossil fuels. Air for combustion is taken from the immediate water heater location or is ducted in from the outside (see “Combustion Air Supply and Ventilation” section).

This water heater must be properly vented for the removal of exhaust gases to the outside atmosphere. Correct installation of the vent pipe system is mandatory for the proper and efficient operation of this water heater and is an important factor in the life of the unit.

The vent pipe must be installed according to all local and state codes or, in the absence of local and state codes, the “National Fuel Gas Code”, ANSI Z223.1(NFPA 54)-current edition. The vent pipe installation must not be obstructed so as to prevent the removal of exhaust gases to the outside atmosphere.

IMPORTANT: The use of vent dampers is not recommended by the manufacturer of this water heater. Although some vent dampers are certified by CSA International, this certification applies to the vent damper device only and does not mean they are certified for use on this water heater.

U.L. recognized fuel gas and carbon monoxide (CO) detectors are recommended in all applications and should be installed using the manufacturer’s instructions and local codes, rules, or regulations.

IMPORTANT: If you lack the necessary skills required to properly install this venting system, you should not proceed, but get help from a qualified person.

Draft Hood Installation

Align the legs of the draft hood with the slots provided. Insert the legs and secure the draft hood to the water heater’s top with the four screws provided as shown in Figure 9. Do not alter the draft hood in any way. If you are replacing an existing water heater, be sure to use the new draft hood supplied with the water heater. IMPORTANT: 50K models must use the supplied 4” draft hood. See Figure 9.

Vent Pipe Size

It is important that you follow the guidelines in these instructions for sizing a vent pipe system. If a transition to a larger vent size is required, the vent transition connection must be made at the draft hood outlet.

10

Figure 9

Draft hood Installation

Sheet Metal Screws (four provided)

Legs Draft hood

Legs

	Slot		Slot
			Jacket top
3”- 4” Draft Hood		Install the draft hood with
Combination		the four screws provided.

Sheet Metal Screws (four provided)

Legs	Draft hood
	Legs

Slot		Slot
		Jacket top
4” Draft Hood	Install the draft hood with
(50K Models)	the four screws provided.

Vent Connectors

1.Type B, Double wall, U.L. Listed Vent Pipe.

2.Single wall Vent Pipe.

Maintain the manufacturer’s specified minimum clearance from combustible materials when using type B double wall vent pipe.

Vent connectors made of type B, double wall vent pipe material may pass through walls or partitions constructed of combustible material if the minimum listed clearance is maintained.

Maintain a six inch minimum clearance from all combustible materials when using single wall vent pipe.

IMPORTANT: Single wall vent pipe cannot be used for water heaters located in attics and may not pass through attic spaces, crawl spaces or any confined or inaccessible location. A single wall metal vent connector cannot pass through any interior wall.

When installing a vent connector, please note the following:

•Install the vent connector avoiding unnecessary bends, which create resistance to the flow of vent gases.

•Install without dips or sags with an upward slope of at least 1/4-inch per foot.

•Joints must be fastened by sheet metal screws or other approved means. It must be supported to maintain clearances and prevent separation of joints and damage.

•The length of the vent connector cannot exceed 75% of the vertical vent height.

•The vent connector must be accessible for cleaning, inspection, and replacement.

•Vent connectors cannot pass through any ceiling, floor, firewall, or fire partition.

•It is recommended (but not mandatory) that a minimum 12 inches of vertical vent pipe be installed on the draft hood prior to any elbow in the vent system to improve conditions for positive flow of venting gases.

IMPORTANT: Existing vent systems must be inspected for obstructions, corrosion, and proper installation.