A.O. Smith BTX-80 Operation Manual Download Page 13

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VENT ATTENUATION ASSEMBLY

INSTALLATION INSTRUCTIONS

The Vent Attenuation Assembly (VAA) is designed to provide a
reduction in noise that may be transmitted through the vent pipe.
This installation of this VAA is optional. Review directions
thoroughly prior to installing the new VAA. Please contact the
manufacturer of the water heater as shown in the instruction
manual with any questions or for additional product support.

VENT ATTENUATION ASSEMBLY KIT PARTS LIST

The kit consists of the following items. If a part is missing, use the
contact information in the instruction manual to acquire missing
component(s).

• Vent Attenuation Assembly
• flexible tubing
• hose barb
• hex plug (installed on VAA)
• instruction sheet

VENT ATTENUATION ASSEMBLY INSTALLATION

The VAA is designed for both vertical and horizontal installations.
The vertical installation does not require the additional hose barb
and flexible tubing. However, the horizontal installation will require
the hose barb and flexible tubing to release condensate buildup
from the VAA. See instructions and diagrams that follow for a
more detailed description.

Vertical VAA Installations (Recommended)

1. The VAA is designed to accept two inch PVC pipe into the

adapters on both ends. The VAA can be installed to the piping
from either side (there is no specific inlet or outlet). For optimum
performance, install VAA as close as possible to the blower
assembly.

2. Use standard PVC cement (not included with kit) and glue the

two inch PVC pipe coming from the blower into the VAA.

3. Perform the same sequence on the PVC pipe coming from

the exhaust side (vent terminal side) of the VAA.

4. Make sure the VAA and vent pipe is supported securely to a

permanent fixture (stud or wall). Use standard support straps
(not supplied with kit) that may be found at a local hardware
store. Failure to properly support the VAA and the surrounding
vent pipe could create a hazardous situation. DO NOT puncture
any surface of the VAA.

5. Confirm that the hex plug is securely installed in the 1/2" fitting

found on the center of the VAA pipe. It is imperative that the
plug is secure and air tight to prevent any combustion gases
escaping into the room. If the plug is not securely tightened,
remove and reinstall using Teflon tape on the threads. Once
installed along with the rest of the vent configuration, make
sure to operate the unit through at least one heat up cycle to
ensure there is no leakage around the plug or any joints of the
VAA or vent pipe system.

FIGURE 10: Typical Vertical Installation

Horizontal VAA Installations

1. The VAA is designed to accept two inch PVC pipe into the

adapters on both ends. The VAA can be installed to the piping
from either side (there is no specific inlet or outlet). For optimum
performance, install the VAA as close as possible to the blower
assembly.

2. Use standard PVC cement (not included with kit) and glue

the two inch PVC pipe coming from the blower into the
VAA.

MAKE SURE THE 1/2" FITTING IS ON THE BOTTOM

SIDE OF THE VAA.

This will be used to run the condensate

hose to a suitable drain. See typical vent installation in
Figure 11.

3. Perform the same sequence on the PVC pipe coming from

the exhaust side (vent terminal side) of the VAA.

4. Make sure the VAA and vent pipe is supported securely to a

5. Remove hex plug from the center pipe of the VAA. Locate

the hose barb and install into the 1/2" fitting on the center of
the VAA. Using Teflon tape on the threads, install hose barb
into 1/2" fitting securely. It is imperative that the hose barb is
secure and tight to prevent any combustion gases escaping
into the room.

6. Locate flexible tubing. Slide one end of tube over the hose

barb located on the center pipe of the VAA. The ridges on the
hose barb should prevent the tube from sliding off, however,
to ensure there are no leaks and possible dislocation from
hose barb, use a wire tie or hose clamp (not supplied with kit)
and secure.

7. Take the other end of the flexible tubing and form an 8 inch

diameter circle approximately 3 feet down from the hose barb
located in the VAA. To ensure that the circle (loop) maintains
its shape, use two wire ties (not supplied with kit) to secure it.