A.O. Smith VB/VW- 1000 Special Installation Considerations, Venting System Using AL 29-4C

VENTING

VENT SIZING, INSTALLATION AND TERMINATION SHALL BE IN ACCORDANCE WITH THIS INSTALLATION MANUAL.

ALL ELECTRICAL POWER AND GAS MUST BE TURNED OFF PRIOR TO ANY INSTALLATION OF THE VENTING SYSTEM.

Special Installation Considerations

This boiler is a category IV appliance that can be vented using room air for intake combustion air, or direct vented so that all intake air for combustion comes from the outside through a sealed pipe. When installing this boiler as direct vent, special vent kits are required.

In cold climates any water vapor remaining in the flue gases will condense

into a cloud of vapor at the point where the vent system exits the building. Specialconsiderationisrecommended,beforelocatingtheventtermination near walkways, windows and building entrances.

Direct venting into dead spaces such as alleys, atriums, and inside

corners can cause recirculation of flue gases. Recirculation of flue

gases will cause sooting, premature failure of the heat exchanger, and icing of the combustion air intake during severe cold weather.

To prevent the recirculation of flue gases, maintain as much

distance as possible between the combustion air intake and the

exhaust vent terminal. Due to large volumes of flue gases, multiple

boiler applications also require additional distance between the intake and exhaust terminals.

Venting System Using AL 29-4C®

This boiler may be installed in four separate orientations depending on the requirements­ of the building and the appliance. The installer must decide which method is most appropriate­ for each installation. These orientations are:

1.Vertical Termination - vertical vent termina­tion­ through un- enclosed or en­closed areas with roof penetration, see Figure 11.

2.Through-the-Wall Termination (TWT) - horizontal­ vent termination directly through an outside wall, see Figure 11A.

3.Horizontal Direct Vent - using TWT to exhaust flue products­ and PVC piping to bring combus­tion air to the boiler from the outside, see Figures 12 and 12C.

4.Vertical Direct Vent - using a vertical vent termination to exhaust flue products and PVC piping to bring combustion air to the boiler from outside, see Figures 12A and 12B.

GeneralExhaustVentInstallationProcedure

Prior to beginning the installation of the vent system, determine­ and obtain all parts re­quired for the installa­tion. If this installation is aDirect VentinstallationaDirect Vent Kitis required. Refer to the parts list for kit number.

Proper operation of the boiler and venting­ system is dependent upon use of all specified­ parts and installation­ techniques;­ both safety and proper performance­ of the system may suffer if instructions are not followed.

Connecting Vent to Boiler

Referring to Figure 10., combustion gases are vented using AL29- 4C material. Transition from the horizontal outlet to a vertical vent is achieved through the use of a boot-tee and drain cover or other engineering approved arrangement. A support bracket should be located at the transition point.

The drain connection is necessary for the removal of condensate which may form in the stack. A rubber hose 3/8” ID and 10 feet long is provided for directing the condensate to a suitable drain.

1.Attach the Boot Tee Drain Cover to the appropriate leg of the Boot-Tee, see Figure 10.

2.A trap loop must be formed into the drain tube simply by looping the tube to a minimum 3 inch (76mm) diameter and secure the loop with a cable tie, see Figure 10.

3.Prior to final assembly the trap loop must be “primed” by pouring a small quantity­ of water into the drain hose.

4.Connect the Boot-Tee and Drain Tee assembly­ (or engineering approved equivalent) to the boiler vent connector, see Figure 10.

5.Attach the hose to the drain fitting and run the hose to a sanitary sewer drain maintaining the proper trap loop and following all local, state and federal codes and regulations for draining of acidic effluent (condensate).

Figure 10.

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