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Troubleshooting Guide
Start Up Conditions
THERHAL EXPANSION
"_Tater supply systems may, because of high line pressure, fre-
quent cut-offs, the effects of water hammer and 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 sys-
tem to be closed. As water is heated, it expands (thermal expan-
sion) and closed systems do not allow for the expansion of heat-
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 tempera-
ture-pressure relief valve is not intended for the constant
rdief of thermal expansion. This is an unacceptable condition
and must be corrected.
It is recommended that any devices installed which could create
a closed system have a by-pass and/or the system have an expan-
sion tank to relieve the pressure built by thermal expansion in
the water system. Expansion tanks are available for ordering
through the Sears Service Center. Contact the local plumbing
inspector, water supplier, and/or the Sears Service Center for
assistance in controlling these situations.
HOT COLD
WATER HEATER
COLD WATER
INLET FITTING
WATER HEATER
COLD WATER
INLET FITTING
0)
EXPANSION
TANK
0)
PRESSURE
REDUCING
VALVEWITH
BY-PASS
(_
PRESSUREGAUGE
WATER
SHUTOFF
RECOHMENDED INSTALLATION
(VERTICAL MOUNTING)
FLOOR, CEILING
JOIST,ETC.
STRAPPING
Thermal Expansion Tank Specifications
Model ]'Iknk Capacity
Number [ In Gallons
Dimensions in Inches
Diameter Length
8 inches 12_ inches
1! inches i14_ inches I
Pipe Fitting
On Tank
_" Male
g4 Male
Expansion Tank Sizing Chart
i Water Heater Capacity (Gallons)
i
]Inlet*
Water
Pressure
Expansion
Tank i40p si
Capacity
Needed 6_ps!.
LT0.._P..S}
80psi
I
: 30 40
2 2
2 i 2
2 _[ 2
2 5
[- 52 66 7"-_-
2 5 5
I
2 5 ! 5
5 5 5.....
5 5
55 5 5
*Highest recorded inlet water pressure m 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 tanks air pressure must be adjusted to match that
pressure, but must not be higher than 80 psi.
O)
EXPANSION
O)
PRESSURE
REDUCING INLET COL
VALVE WITH WATER
BY-PASS SHUTOFF
PRESSURE GAUGE
ALTERNATE RECOMMENDED
INSTALLATION
(HORIZONTAL MOUNTING)
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 heat!ng and coolin,g periods and shouId be considered
normal. See Condensation section.
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