A.O. Smith 104 Series, Instruction Manual

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19
Where an existing F himney or vent is to be used, be sure
that the F himney or vent has adequate F apa F ity for the
number and sizes of gas applian F es being vented through
it Inspe F t the F himney or vent and remove all soot or other
obstru F tions whi F h will retard free draft
Vent F onne F tors making horizontal runs must have a minimum
upward slope toward the F himney or vent of 1/4 in F h per foot
Vent F onne F tor length should be kept as short as possible
Be sure that the vent pipe does not extend beyond the inside
wall of a
F himney
In venting systems where a F ontinuous or intermittent
ba F k (positive) draft is found to exist, the F ause must
be determined and F orre F ted In some F ases, a spe F ial
vent F ap may be required Do not install this unit on the
positive draft side of a venting system being served by a
power exhauster
WATER HEATER INSTALLATION
VENT CONNECTION
Vent F onne F tions must be made to an adequate sta F k
or F himney Refer to the National Fuel Gas Code ( F urrent
edition) or to the vent pipe manufa F turer ¶ s gas vent and
F himney sizing table to properly design and size the venting
system Refer to Table 7 for the vent pipe size required for
installation to the barometri F draft F ontrol assembly outlet
TABLE 7. BAROMETRIC DRAFT CONTROL
ASSEMBLY OUTLET SIZE
MODEL
DRAFT CONTROL
OUTLET DIAMETER
BTP-139/A
BTP-199/A
BTP-270/A
BTP-370/A 6 ´
6 ´
8 ´
8 ´
WATER PIPING DIAGRAMS
This manual provides detailed water piping diagrams for typi F al
methods of appli F ation for the water heaters, see Water Piping
Diagrams beginning on page 35
The water heater may be installed by itself, or with a separate
storage tank
When used with a separate storage tank, the
F ir F ulation may be either by gravity or by means of F ir F ulating
pump Adjust À ow by throttling a full port ball valve installed in the
F ir F ulating line on the outlet side of the pump Never throttle À ow
on the su F tion side of a pump See the Water Piping Diagrams
beginning on page 35
NOTE: In addition to the fa F tory installed Temperature-Pressure
Relief Valve (T&P valve) on the water heater, ea F h remote
storage tank that may be installed and piped to a water heating
applian
F e must also have its own properly sized, rated and
approved Temperature-Pressure Relief Valve installed
Call the toll free te F hni F al support phone number listed on the
ba F k F over of this manual for further assistan F e in sizing a T&P
valve for remote storage tanks
T&P VALVE DISCHARGE PIPE
Explosion Hazard
Temperature-Pressure Relief Valve
must comply with ANSI Z21.22-
CSA 4.4 and ASME code.
Properly sized temperature-
pressure relief valve must be
installed in opening provided.
Can result in overheating and
excessive tank pressure.
Can cause serious injury or death.
WATER LINE CONNECTIONS
The water piping installation must F onform to these instru F tions
and to all lo F al F ode authority having jurisdi F tion Good pra F ti F e
requires that all heavy piping be supported
Read and observe all requirements in the following se F tions
before installation of the water piping begins
1 Water Temperature Control and Mixing Valves on page 13
2 Dishwashing Ma F hines on page 14
3 Temperature-Pressure Relief Valve on page 14-15
4 Closed Systems and Thermal Expansion on page 14
5 For multiple water heater installations see Water Piping
Diagrams beginning on page 35
WATER (POTABLE) HEATING AND SPACE HEATING
1 All piping F omponents F onne F ted to this unit for spa F e
heating appli F ations shall be suitable for use with potable
water
2 Toxi F F hemi F als, su F h as those used for boiler treatment,
shall NEVER be introdu F ed into this system
3 This unit may NEVER be F onne F ted to any existing heating
system or F omponent(s) previously used with a non-potable
water heating applian F e
4 When the system requires water for spa F e heating at
temperatures higher than required for domesti F water
purposes, a tempering valve must be installed Please
refer to installation diagrams beginning on page 35 of this
manual for suggested piping arrangements
5 These water heaters F annot be used in spa F e heating
appli F ations only
THERMOMETERS (NOT SUPPLIED)
Thermometers should be obtained and ¿ eld installed as shown
in the installation diagrams
Thermometers are installed in the system as a means of
dete
F ting the temperature of the outlet water supply