A.O. Smith 104 Series, Инструкция по эксплуатации

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14
HOT WATER
OUTLET
TO TANK
INLET
CHECK
VALVE
MIXING
VALVE
COLD
WATER
INLET
TEMPERED WATER
OUTLET
12” TO 15”
(30-38 cm)
CHECK
VALVE
FIGURE 10.
DISHWASHING MACHINES
All dishwashing ma F hines meeting the National Sanitation
Foundation requirements are designed to operate with water
flow pressures between 15 and 25 pounds per square in
F h
(103 kPa and 173 kPa) Flow pressures above 25 pounds
per square in F h (173 kPa), or below 15 pounds per square
in F h (103 kPa), will result in improperly sanitized dishes
Where pressures are high, a water pressure redu F ing or flow
regulating F ontrol valve should be used in the 180 ƒ F (82 ƒ C)
line to the dishwashing ma F hine and should be adjusted to
deliver water pressure between these limits
The National Sanitation Foundation also re F ommends
F ir F ulation of 180 ƒ F (82 ƒ C) water The F ir F ulation flow rate
should be just enough to provide 180 ƒ F (82 ƒ C) water at the
point of take-off to the dishwashing ma F hine
Adjust flow by throttling a full port ball valve installed in
the
F ir F ulating line on the outlet side of the pump Never
throttle flow on the su F tion side of a pump See Water Piping
Diagrams in this manual
CLOSED WATER SYSTEMS
Water supply systems may, be F ause of F ode requirements or
su F h F onditions as high line pressure, among others, have
installed devi F es su F h as pressure redu F ing valves, F he F k
valves, and ba F k flow preventers Devi F es su F h as these
F ause the water system to be a F losed system
THERMAL EXPANSION
As water is heated, it expands (thermal expansion) In a
F losed system the volume of water will grow when it is heated
As the volume of water grows there will be a F orresponding
in F rease in water pressure due to thermal expansion Thermal
expansion F an F ause premature tank failure (leakage) This
type of failure is not F overed under the limited warranty
Thermal expansion F an also F ause intermittent Temperature-
Pressure Relief Valve operation water dis F harged from the
valve due to ex F essive pressure build up This F ondition is
not F overed under the limited warranty The Temperature-
Pressure Relief Valve is not intended for the F onstant relief
of thermal expansion
A properly sized thermal expansion tank must be installed on
all
F losed systems to F ontrol the harmful effe F ts of thermal
expansion Conta F t a lo F al plumbing servi F e te F hni F ian to have a
thermal expansion tank installed
See Water Line Conne F tions on page 19 and the Water Piping
Diagrams beginning on page 35
TEMPERATURE-PRESSURE RELIEF VALVE
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.
This water heater is provided with a properly rated/sized and F erti ¿ ed
F ombination Temperature-Pressure Relief Valve (T&P valve) by
the manufa F turer The valve is F erti ¿ ed by a nationally re F ognized
testing laboratory that maintains periodi F inspe F tion of produ F tion
of listed equipment of materials as meeting the requirements for
Pressure Relief Valves for Hot Water Supply Systems, ANSI Z21
22
‡ CSA 4 4, and the F ode requirements of ASME
If repla F ed, the new T&P valve must meet the requirements
of lo F al F odes, but not less than a F ombination Temperature-
Pressure Relief Valve rated/sized and F erti ¿ ed as indi F ated in
the above paragraph The new valve must be marked with a
maximum set pressure not to ex F eed the marked hydrostati F
working pressure of the water heater (150 psi 1,035 kPa) and
a dis F harge F apa F ity not less than the water heater Btu/hr or kW
input rate as shown on the water heater ¶ s model rating label
NOTE In addition to the fa F tory installed Temperature-Pressure
Relief 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 te F hni F al assistan F e in sizing a Temperature-Pressure Relief
Valve for remote storage tanks
For safe operation of the water heater, the Temperature-Pressure
Relief Valve must not be removed from its designated opening
nor plugged
The Temperature-Pressure Relief Valve must be
installed dire F tly into the ¿ tting of the water heater designed for
the pressure relief valve Install dis F harge piping so that any
dis F harge will exit the pipe within 6 in F hes (15 2 F m) above an
adequate À oor drain, or external to the building In F old F limates
it is re F ommended that it be terminated at an adequate drain
inside the building Be F ertain that no F onta F t is made with any
live ele F tri F al part The dis F harge opening must not be blo F ked
or redu F ed in size under any F ir F umstan F es Ex F essive length,
over 30 feet (9 14 m), or use of more than four elbows F an F ause
restri F tion and redu F e the dis F harge F apa F ity of the valve