Rheem Double Element Residential Electric Models, Инструкция по использованию и уходу

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6
Typical Installation
R E
L I
E F
V A
L V
E
H
O
T
C O
L D
To cold water supply*
Jacket access panel
Relief valve discharge line to
suitable open drain
Drain valve
Electrical junction box (inside jacket)
Hot water outlet
to fixtures
Anode
Shut-off valve
Union
Temperature &
pressure relief valve
Thermal expansion tank
(if required)
Heat trap 15 cm (6
″
)
minimum
15 cm (6
″
) air gap
Heat trap 15 cm (6
″
)
minimum
Auxiliary catch pan
5 cm (2’) maximum
To electrical
distribution panel
Jacket access panel
Union
Installing the water heater.
Thermal Expansion
Determine if a check valve exists in the inlet water line. It may have been installed
in the cold water line as a separate back flow preventer, or it may be part of a pressure reducing
valve, water meter or water softener. A check valve located in the cold water inlet line can
cause what is referred to as a “closed water system” . A cold water inlet line with no check
valve or back flow prevention device is referred to as an “open” water system.
As water is heated, it expands in volume and creates an increase in the pressure within
the water system. This action is referred to as “thermal expansion” . In an “open” water
system, expanding water which exceeds the capacity of the water heater flows back into
the city main where the pressure is easily dissipated.
A
“closed water system” , however, prevents the expanding water from flowing back into the
main supply line, and the result of “thermal expansion” can create a rapid and dangerous
pressure increase in the water heater and system piping. This rapid pressure increase can
quickly reach the safety setting of the relief valve, causing it to operate during each heating
cycle. Thermal expansion, and the resulting rapid and repeated expansion and contraction of
components in the water heater and piping system can cause premature failure of the relief
valve, and possibly the heater itself. Replacing the relief valve will not correct the problem!
The suggested method of controlling thermal expansion is to install an expansion tank in the
cold water line between the water heater and the check valve (refer to the illustration below).
The expansion tank is designed with an air cushion built in that compresses as the system
pressure increases, thereby relieving the over pressure condition and eliminating the repeated
operation of the relief valve. Other methods of controlling thermal expansion are also available.
Contact your installing contractor, water supplier or plumbing inspector for additional
information regarding this subject.
NOTICE: Do not apply heat to
the HOT or COLD water
connections. If sweat
connections are used, sweat
tubing to adapter before
fitting adapter to the water
connections on heater. Any
heat applied to the water
supply fittings will
permanently damage the dip
tube and or heat traps.
Water Supply Connections
Refer to the illustration below for suggested typical installation. The installation of unions or
flexible copper connectors is recommended on the hot and cold water connections so that the
water heater may be easily disconnected for servicing if necessary. The HOT and COLD
water connections are clearly marked and are 3/4
″
NPT on all models. Install a shut-off valve
in the cold water line near the water heater.
To cold water supply*
* Some models are
constructed with a side
cold water inlet and will
not have an opening on
the top of the water
heater.