A.O. Smith 104 Series, Инструкция по эксплуатации

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4 When installing multiple water heaters in the same gas supply
system it is re F ommended that individual positive lo F k-up gas
pressure regulators be installed at ea F h unit
POWER SUPPLY
The water heaters F overed in this manual require a 120 VAC,
1Ø (single phase), 60Hz, 15 amp power supply and must also
be ele
F tri F ally grounded in a FF ordan F e with lo F al F odes or, in the
absen F e of lo F al F odes, with the National Ele F tri F al Code, ANSI/
NFPA 70 or the Canadian Ele F tri F al Code, CSA C22 1
WATER TEMPERATURE CONTROL AND MIXING VALVES
Water temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the
physically or mentally disabled are at
highest risk for scald injury.
Feel water before bathing or showering.
Temperature limiting devices such as
mixing valves must be installed
when required by codes and to
ensure safe temperatures at fixtures.
Water heated to a temperature whi F h will satisfy F lothes washing, dish
washing, and other sanitizing needs F an s F ald and F ause permanent
injury upon F onta F t Short repeated heating F y F les F aused by small
hot water uses F an F ause temperatures at the point of use to ex F eed
the water heater ¶ s temperature setting by up to 20 ƒ F (11 ƒ C)
Some people are more likely to be permanently injured by hot water
than others
These in F lude the elderly, F hildren, the in ¿ rm and the
physi F ally/mentally disabled Table 6 shows approximate time-to-burn
relationship for normal adult skin If anyone using hot water provided
by the water heater being installed ¿ ts into one of these groups or if
there is a lo F al F ode or state law requiring a F ertain water temperature
at the point of use, then spe F ial pre F autions must be taken
In addition to using the lowest possible temperature setting that
satis
¿ es the demand of the appli F ation a Mixing Valve should be
installed at the water heater (see Figure 10) or at the hot water taps
to further redu
F e system water temperature
Mixing valves are available at plumbing supply stores Consult a
Quali ¿ ed Installer or Servi F e Agen F y Follow mixing valve manufa F turer ¶ s
instru F tions for installation of the valves
TABLE 6.
Water Temperature ƒ F
Time for 1st Degree Burn
(Less Severe Burns)
Time for Permanent Burns
2nd & 3rd Degree
(Most Severe Burns)
110 (normal shower temp )
116 (pain threshold)
116 35 minutes 45 minutes
122 1 minute 5 minutes
131 5 se F onds 25 se F onds
140 2 se F onds 5 se F onds
149 1 se F ond 2 se F onds
154 instantaneous 1 se F ond
(U S Government Memorandum, C P S C , Peter L Armstrong, Sept 15,1978)
GAS SUPPLY SYSTEMS
Low pressure building gas supply systems are defined as those
systems that
F annot under any F ir F umstan F es ex F eed 14 ´
W C (1/2 PSI Gauge) These systems do not require pressure
regulation Measurements should be taken to insure that gas
pressures are stable and fall within the requirements stated on
the water heater rating plate
Readings should be taken with
all gas burning equipment off (stati F pressure) and with all gas
burning equipment running at maximum rate (dynami F pressure)
The gas supply pressure must be stable within 1 5 ´ W C
from stati F to dynami F pressure to provide good performan F e
Pressure drops that ex F eed 1 5 ´ W C may F ause rough starting,
noisy F ombustion or nuisan F e outages In F reases or spikes
in stati F pressure during off F y F les may F ause failure to ignite
or in severe F ases damage to applian F e gas valves If your
low pressure system does NOT meet these requirements, the
installer is responsible for the
F orre F tions
High Pressure building supply systems use pressures that
ex
F eed 14 ´ W C (1/2 PSI Gauge) These systems must use ¿ eld
supplied regulators to lower the gas pressure to less than 14 ´
W C (1/2 PSI Gauge) Water heaters require gas regulators that
are properly sized for the water heater input and deliver the rating
plate spe
F i ¿ ed pressures Gas supply systems where pressure
ex F eeds 5 PSI often require multiple regulators to a F hieve desired
pressures Systems in ex F ess of 5 PSI building pressure should
be designed by gas delivery professionals for best performan F e
Water heaters F onne F ted to gas supply systems that ex F eed 14 ´
W C (1/2 PSI Gauge) at any time must be equipped with a gas
supply regulator
All models require a minimum gas supply pressure of 4 5" W C
for natural gas and propane gas The minimum supply pressure
is measured while gas is À owing (dynami F pressure) The supply
pressure should never fall below 4 5" W C for natural gas and
propane gas The supply pressure should be measured with all
gas ¿ red applian F es F onne F ted to the F ommon main ¿ ring at full
F apa F ity If the supply pressure drops more than 1 5 ´ W C as gas
begins to À ow to the water heater then the supply gas system
in F luding the gas line and/or the gas regulator may be restri F ted
or undersized See Supply Gas Regulator se F tion and Gas
Piping se F tion of this manual The gas valve on all models has
a maximum gas supply pressure limit of 14 ´ W C The maximum
supply pressure is measured while gas is not À owing (stati F
pressure)
SUPPLY GAS REGULATOR
The maximum allowable gas supply pressure for this water heater is
14" W
C (3 48 kPa) Install a positive lo F k-up gas pressure regulator
in the gas supply line if inlet gas pressure F an ex F eed 14" W C
(3 48 kPa) at any time Regulators must be sized/used a FF ording to
manufa F turer ¶ s spe F i ¿F ations
If a positive lo F k-up regulator is required follow these instru F tions
1 Positive lo F k-up gas pressure regulators must be rated at or above
the input Btu/hr rating of the water heater they supply
2 Positive lo F k-up gas pressure regulator(s) should be installed no F loser
than 3 equivalent feet (1 meter) and no farther than 8 equivalent
feet (2 4 meters) from water heater ¶ s inlet gas F onne F tion
3 After installing the positive lo F k-up gas pressure regulator(s), an
initial nominal supply pressure setting of 7" W C (1 74 kPa) while
water heater is operating is re F ommended and will generally
provide good water heater operation Some additional adjustment
maybe required later to maintain a steady gas supply pressure
INSTALLATION REQUIREMENTS