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Troubleshooting Guide
Start Up Conditions
THERMAL EXPANSION
Water supply systems may, because of such events as high line
pressure, frequent cut-offs, the effects of water hammer _mong
others, 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 other measures are taken, the devices cause the
water system to be closed. As water is heated, it expands (ther-
mal expansion) and closed systems do not allow for the expan-
sion of heated 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 reacfied, the
valve will relieve the excesspressure. The temperature-pressure
relief valve is not intended'for the constant relief of thermal
expansion. This is an unacceptable condition and must be cor-
rected.
It is recommended that any devices installed which could create a
dosed system have a by-pass and/or the system have an expan-
sion tank to relieve the pre_ure built by thermal expansion.
Thermal expansion tanks ar'e available from Sears stores and
through the Sears Service Centers. Contact the local plumbing
inspector, water supplier and/or the Sears Service Center for
assistance in controlling these situations.
Thermal Expansion Tank Specifications
Model Tank Capacity Dimensions in Inches Pipe Fitting
Number In Gallons Diameter Length On Tank
153.331020 2 8 inches 12_inches _" Male
153.331050 5 11inches 14_inches _" Male
HOT
COLD
WATER HEATER
COLD WATER
INLET FITTING
WATERHEATER
COLDWATER
,INLETFII-nNG
(t)
EXPANSION
TANK
PRESSURE
REDUCING
VALVEWITH
BY-PASS
(z)
PRESSUREGAUGE
WATER
SHUTOFF
RECOMMENDED INSTALLATION
(VERTICAL MOUNTING)
FLOOR,CEIUNG
lOb-n;ETC.
STRAPPING
0)
PRESSURE
REDUCING
VALVEWITH
(I) BY-PASS
EXPANSION
INLET COLD
WATER
SHUTOFF
Expansion Tank Sizing Chart
Water Heater Capacity (Gallons)
Inlet*
Water
Pressure
40psi
50psi
60psi
70psi
80psi
Expansion 30 40 50 66 82
Tank 2 2 2 5 5
Capacity 2 2 2 5 5
Needed 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 me 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.
(z)
PRESSUREGAUGE
ALTERN.A.TERECOMMENDED
INSTALLATION
(NC?PJZONTALMOUNTING)
STRANGE SOUNDS
Possible noises due to expansion and contraction of some metal
parts during periods of heat-up and cool-down do not represent
harmful or dangerous conditions.
Condensation causes sizzling and popping with the burner area
during heating and cooling periods and should be considered
normal. See "Condensation" section.
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