Mounting The Heater - Bosch 125HX LP Installation And Operating Instructions Manual

13 ¼"
Fig. 1 - Mounting the Heater
The incandescent particle tray (shipped loose in the carton
with the water heater) must be attached at the bottom of
the water heater front cover at the time of installation. Use
the screws provided. See figure 2
Fig. 2 - Incandescent Particle Tray Illustration
VENTING
Vent pipe connection. WARNING: Do not reduce
the vent pipe size.
This appliance must be vented to the outside following all
local ordinances and specifications for installing a gas
appliance vent or chimney. The venting system must be
designed and constructed so as to develop a positive flow
adequate to remove flue gasses to the outdoors. Minimum
vent size must be 5". Minimum vent height must be 6
feet, provided there are no elbows. Termination of
the vent must be 2 feet above any obstruction within
a 10 foot radius of the vent pipe. Consult your gas
utility or National Gas Fuel Code if vent will have
elbows or share venting with another appliance. The
vent connector should have as much vertical rise as
possible (minimum 12") before any horizontal run.
Optional powervent available in order to sidewall vent.
Contact your local dealer. The appliance must be located
as close as practicable to a chimney or vent. The vent pipe
sections must be secured to each other with sheet metal
screws. Keep in mind the minimum clearance from the top
of your heater. Remember also that single wall vent pipe
connectors require a 6 inch clearance from combustibles.
National Fuel Gas Code specifies double wall — Type "B"
— vent pipe be used in cold climates and for gas vents
running through attics. We consider double wall vent pipe
preferable in all circumstances. Any vent section greater
than 45 degrees from vertical is considered horizontal.
Horizontal sections of vent connectors must slope upwards
6
WALL STUDS
SUPPORT BOARD
1" X 4"
SPACE BOARD
SCREWS
INCANDESCENT PARTICLE TRAY
at least 1/4 inch for every foot of its horizontal length. Keep
the horizontal section short and avoid too many elbows.
To check the draft:
Close all doors and windows to the outside.
Turn on all appliances that force air out of the building.
These include all exhaust/ventilation fans, furnaces, clothes
dryers, wood burning stoves, etc.
Open all doors between the AquaStar and these other
appliances.
Run the unit for at least 10 minutes. Then hold an ordinary
mirror at the side above the front shell. Any flue gases
backdrafting will cause the mirror to fog. This is a serious
health hazard and must be corrected. Poor venting can
result in soot building up inside the heater, overheating of
the heater and freezing of the heat exchanger in a freezing
environment.
The mirror will remain clear with a properly functioning draft.
WARNING
Note: The burners of an instantaneous "on demand" water
heater such as the AquaStar are only on at the time that
hot water is actually being used, the vent pipe is therefore
cold except for the short durations when hot water is being
used, it is therefore very important that the venting and air
supply be adequate to provide a good positive draft as
soon as the burners turn on. See venting guide on back
page.
The AquaStar 125HX instantaneous water heaters have built-
in draft diverters and are designed for indoor installation
only. The draft diverter outlet must be connected to a clear,
unobstructed vent of the same size, or larger.
In Canada, CAN/CGA-B149 Installation Code for detailed
requirements
In U.S.A., ANSI Z223.1 - NFPA 54, national Fuel Gas
Code for detailed requirements.
The vent connection for the AquaStar 125HX is 5 inches.
However, in CANADA, for installations at high altitude (2000-
4500 feet above sea level) a six inch vent is required. A 5"
by 6" vent adaptor must be affixed to the vent collar of the
AquaStar with at least two screws. See figure 3.
WARNING: Failure TO INCREASE THE VENT SIZE
TO SIX INCHES AND/or assure that the manifold pressure
is set to proper value listed for applications at high altitudes
will cause unsafe venting, asphyxiation, and will void CSA
Certification.
Fig. 3 - Vent Adaptor for High Altitude Canadian
Installations
5" X 6" ADAPTOR
USED ON HIGH ALTITUDE
6 720 606 562 (02.03)