Filter
Top Products
Start Up Conditions
Thermal Expansion
Property Damage Hazard
• Avoid water heater damage.
• Install thermal expansion tank or device if necessary.
• Contact qualified installer or service agency.
As water is heated, it expands (thermal expansion). In a closed
system, the volume of water wilt grow. As the volume of water
grows, there wilt be a corresponding increase in water pressure
due to thermal expansion. Thermal expansion can cause
premature tank failure (leakage). This type of failure is not
covered under the limited warranty. Thermal expansion can also
cause intermittent temperature-pressure relief valve operation:
water discharged from the valve due to excessive pressure build
up. The temperature-pressure relief valve is not intended for the
constant relief of thermal expansion. This condition is not covered
under the limited warranty.
A properly-sized thermal expansion tank should be installed
on all closed systems to control the harmful effects of thermal
expansion. Contact a plumbing service agency or your retail
supplier regarding the installation of a thermal expansion tank.
Table 1 : Thermal Expansion Tank Specifications
Model
Number
153.331020
153.331050
Tank
Capacity
In Gallons
2
5
Dimensions
in inches
Diameter Len£1th
8 (203 mm) 12-3/4 (323 mm)
11(279 mm) 14-3/4 (375 mm)
Pipe
Fitting
On Tank
3/4" Male
3/4" Male
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.
HOT COLD
WATER HEATER (3)
COLD WATER PRESSURE
INLET FITTING REDUCING
VALVE WITH
BY-PASS
(2)
PRESSURE GAUGE
INLET COLD
WATER SHUT-OFF
RECOMMEN DED INSTALLATION
(VERTICAL MOUNTING)
WATER HEATER
COLD WATER
INLET FITTING
HOT
I f
FLOOR, CEILING JOIST, ETC.
COLD STRAPPING
/ t
PRESSURE GAUGE INLET COLD
WATER SHUT-OFF
ALTERNATE RECOMMENDED INSTALLATION
(HORIZONTAL MOUNTING)
Expansion
Tank
Capacity
Needed
Table 2: Expansion Tank Sizing Chart
Inlet* Water Heater Capacity (Gallons)
Water
Pressure
30 40 50 66 82
40 psi 2 2 2 5 5
50 psi 2 2 2 5 5
60 psi 2 2 2 5 5
70 psi 2 2 5 5 5
80 psi 2 5 5 5 5
*Highest recorded inlet water pressure in a 24 hour period or
regulated water pressure.
FIGURE 35.
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 within the burner area
during heating and cooling periods and should be considered
normal. See Condensation section.
Draft Hood Operation
Check draft hood operation by performing a worst case
depressurization of the building. With all doors and windows
closed, and with all air handling equipment and exhaust fans
operating such as furnaces, clothes dryers, range hoods and
bathroom fans, a match flame should still be drawn into the
draft hood of the water heater with its burner firing. If the flame
is not drawn toward the draft hood after 15 minutes of burner
operation, shut off water heater and make necessary air supply
changes to correct.
26