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Troubleshooting Guide
Start Up Conditions
THERMAL EXPANSION
Water supflly systems may, because of such events as high line
pressure, trequent cut-offs, the effects of water hammer among
others, have installed devices such as pressure reducing valves,
check valves, back flowpreventers, etc...to control these types of
problems. When these devices arenot 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 reached, the
valve will relieve the excess pressure. The te.mperaturc-pr_anre
relief valve is not intendedfor the constant relief of thermal
expansion, This is an unacceptable condition and must he 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 pressure built by thermal expansion.
Thermal expansion tanks are 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
Number
153.331020 I
153.331050
Tank Capacity
In Gallons
2
5
Dimensions in Inches
Diameter Length
8 inches 12_ inches
11 inches 14_ inches
Pipe Fitting
On Tank
_" Male
_" Male
HOT
COLD
WATER HEATER
COLD WATER
INLET FITTING
HOT COLD
WATERHEATER O)
COLD WATER PRESSURE
INLET FITTING I_I_UCIIqG
VALVEWITH
BY-PASS
(i) !
EXPANSION
TANK
PRESSUREGAUGE
WATER
SHUTOFF
RECOMMENDED INSTALLATIOH
(VEmlCALMOUN'nNG).
FLOOR, CEILING
jots_,ETC.
O) •
PRESSURE INLET COLD
REDUCING WATER
VALVEWITH SHUTOFF
Expansion Tank Sizing Chart
Expansion
Tank
Capacity
Needed
Inlet*
Water
Pressure
40psi
5092
60psi
70psi
180psi
3_0Water Heater Capacity (Gallons)
2
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 tanks air pressure must be adjusted to match that
pressure, but must not be higher than 80 psi.
PRESSUREGAUGE
AL_TE RECOI,IHENDEO
INSTALLATION
(HORIZONTAL MOUNTING)
STRANGE SOUNDS
Possible noises due to expansion and contraction of some metal
parts during periods of hcat-up and cool-down do not represent
harmful or dangerous conditions.
Condensation causes sizzling and popping with the burner area
during heati n_ and coolin_ periods and should be considered
normal. See Condensation section.
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