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Troubleshooting Guide
Start Up Conditions
THERMAL EXPANSION
Water supply systems may, because of high line pressure, fre-
quent cut-off,s, the effects of water hammer and otbets, have
installed devices such as pressure reducing valves,check valves,
back flow preventers, etc. to control these types of problems.
When these devices are not equipped with an internal by-pass,
and no othermeasuresaretaken, the devicescause the water sys-
tem to be dosed. As water is heated, it expands (thermal expan-
sion) and closed systemsdo not allow for the expansion of beat-
ed water.
The water within the water heater tank expands as it is heated
and increases the pressure of the water system. If the relieving
point of the water heater's temperature-pressure relief valve is
reached, the valve will relieve the excess pressure. The tcmpcra-
ture-preasure relief valve is not intended for the constant
relief of thermal expansion. This is an unacceptable condition
and must be corrected.
It is recommendedthat any devicesinstalledwhich could create
a dosed system have a by-passand/or the system have an expan-
sion tank to relievethe pressure built by thermal expansion in
the water system. Expansion tanks are available for ordering
through the Sears Service Center. Contact the iota[plumbing
inspector, water supplier, and/or the Sears Service Center for
assistancein controlling these situations.
HOT COLD
WATEI_HEATER
COLD WAI_'R
INLETFIT'nNG
HOT
WATER HEATER
COlDW_,TIR (3)
INLET Fn-rlNG pRESSURE
REDUCING
VALVEWITH
WATER
SHUTOFF
RECOMMENDEDINSTALLATION
(VEETtCALMOUNTING)
FLOOR,¢EIUNG
IOIS_,ETC.
STRAPPING
Thermal Expansion Tank Specifications
Model
Number
153.331020
153.331050
Tank Capacity
In Gallons
2
5
Dimensions in Inches
Diameter Length
8 inches 12_ inches
11 inches 14_inches
Pipe Fitting I
On Tank i
_" Male
_" Male
Expansion Tank Sizing Chart
Water HeaterCapacity (Gallons)
Expansion
Tank
Capacity
Needed
Inlet*
Water
Pressure
40psi
50psi
60psi
70psi
80psi
30 40 50 66 82
2 2 2 5 5
2 2 2 5 5
2 2 5 5 5
2 2 5 5 5
2 5 5 5 5
*Highest recorded inlet water pressure in a 24 hour period or
regulated water pressure.
NOTE: Expansion tanks are pre-charged with a 40 psi air
charge. If the inlet water pressure is higher than 40 psi, the
expansion tank's air pressure must be adjusted to match that
pressure, but must not be higher than 80 psi.
(i)
EXPANSION
0)
PRESSURE
REDUCING INLET COLD
VALVE WITH WATER
BY-FASS SHUTOFF
pRESSUk_EGAUGE
ALTERNATE RECOMI_IENDED
INSTALLATION
(HORIZONTAL MOUNTING)
STRANGE SOUNDS
Possiblenoises due to expansion and contraction of some metal
parts duringperiods of heat-up and cool-down do not represent
harmful or dangerousconditions.
Condensation causes sizzlingand popping with the burner area
during heating and cooling periods and should be considered
normal. See "Condensation" section.
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