Bosch AQ4 GWH 1600 P - Manual (Page 5)

5 AQ4 Manual
2 AQ4 Installation instructions
2.1 Introduction
Please follow these instructions. Failure to follow
instructions may result in:
· Damage, injury or death
· Improper operation
· Loss of warranty
If you are unable to perform the tasks required to
install the water heater and this accessory properly,
please contact a locally licensed plumber, HVAC
contractor or gas technician.
Please contact Bosch Water Heating with any
questions.
2.2 Locating power vent hood and
clearances
The maximum vent length from the water heater to
the point of termination is 25 feet with one elbow. If
using more than one 90° elbow, subtract 5 feet off
the maximum vent length for each additional elbow
used. Maximum of three elbows allowed.
The power vent motor must be installed
as close as possible to the VH1-4 vent
hood.
Clearances
The vent system must terminate so that proper
clearances from the center of the vent hood (Fig.
1) are maintained as cited in the National Fuel Gas
Code, ANSI Z223.1 and CSA B149.1 in Canada:
“The vent terminal shall also not be installed closer than 3
feet from the inside corner of an L-shaped structure, or less
than 1 foot above grade or anticipated snow pack level.”
Also:
“The exit terminals of mechanical vent system shall be located
not less than 7 feet above grade when located adjacent to a
public walkway. The venting system shall terminate at least
3 feet above any forced air inlet within 10 feet. The venting
system shall terminate at least 4 feet below, 4 feet horizontally
from or 1 foot above any door, window or gravity air inlet into
any building.”
2.3 Power vent hood
1. Attach the mounting template (on page 14)
to the interior wall that the vent hood will be
penetrating.
2. Ensure that the proposed vent termination
clearances are met (Chapter 2.2) before cutting
opening through wall. Using a 1/2” drill bit, drill
two pilot holes where noted on the template. The
drill bit must be long enough to penetrate to the
building exterior.
3. Attach the template to the outside of the building
aligning the pilot holes on the template with the
pilot holes drilled in step 2.
4. Using a reciprocating saw, cut a hole through the
building siding, wall board, etc., following the
appropriate lines of the template.
5. Apply a bead of exterior-rated caulk to the vent
hood flange to seal at the exterior of building.
6. Slide the vent hood through the opening and
fasten to exterior wall using screws provided.
7. Inspect back draft flapper on hood. If the flapper
does not properly close, there is a risk of freezing
air coming into the water heater causing the pipes
inside to freeze and burst. This condition is not
covered by the water heater warranty. See Fig.
11A for a properly closed back draft flapper.
AQ4 Installation instructions
Fig. 1 External vent hood clearances