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Copper Brute B4 Volume Water Heaters Page 15
2.6.9 Storage Tank Installation
1. Be sure the oor is structurally capable of
supporting the tank when it is lled with water,
and is waterproof.
2. Place the tank so that manholes, inspection
covers, nameplates and drain valves are
accessible.
3. Be sure the tank is suitable for the water in the
system. Some water is corrosive and requires
a protected tank. Most tanks are available with
glass, plastic, or galvanized linings.
4. If the tank is glass-lined, it should be equipped
with a suitable magnesium anode. It is a
good practice to replace the anode when it is
approximately 50 percent used. The factory
warranty on a glass-lined tank may be void if a
satisfactory anode is not in place at the time of a
failure or if it is consumed by cathodic action.
5. The tank must be lined if a water softener is
installed in the system.
6. Make sure the tank connections in the heater-
tank circulating loop are the proper size (see
Section 2.6.5). If tappings are smaller than the
recommended pipe size, a larger pump may be
required. Consult the factory if in doubt.
7. Install a pipe in the tank drain tting that goes to
a oor sink, and install a drain valve. If a oor
sink is not available, install a hose bib.
8. Hot water tanks in an existing installation
are likely to have silt deposits on the bottom.
Therefore, it is important to extend the pump
suction pipe in the tank to a position near the top.
Pipe the return from the heater to the bottom of
the tank.
Incorrect installation can cause rapid failure
of water tanks due to electrolysis. Tanks must
be installed with dialectric connections to
electrically isolate the tank from stray current.
Note that use of brass or bronze connectors does
not replace the need for dialectric connections.
2.6.6 Pressure Buildup in Water System
The water utility supply meter may contain a
check valve, back ow preventer, or water pressure
reducing valve that will create a closed water supply
system. Contact the water supplier or local plumbing
inspector on how to control this situation.
During the heating cycle of the heater, the water
expands creating a pressure buildup in the water
system. The pressure relief valve may discharge hot
water under these conditions, causing a loss/waste of
energy and a buildup of lime on the relief valve seat.
NOTE: Do not plug the relief valve.
There are two methods to prevent the relief valve
from discharging hot water in a closed water system:
1. Install a pressure relief valve on the cold water
supply line. Make sure that the discharge of this
valve is directed to an open drain and protected
from freezing.
2. Install a properly sized thermal expansion tank
on the cold water supply line.
2.6.7 Pressure Relief Valve
The pressure relief valve must be installed in the
tapped opening provided in the boiler header with its
outlet piped to a drain or oor sink. Special attention
must be given to relief valve settings in installations
where the boiler is located on the ground oor of a
tall building, or where the operating temperature of
the boiler is above 210°F. In both instances, the static
pressure of the system is elevated, and could cause
the relief valve to leak. Where no special setting of
the relief valve is ordered, the factory will furnish a
125 psi setting.
WARNING
Hot water can scald! Hot water can produce
third degree burns in 6 seconds at 140°F (60°C)
and in 30 seconds at 130°F (54°C).
2.6.8 Water Pressure
Keep the water pressure in the system above
30 psi (207 kPa). If the system pressure drops below
30 psi (207 kPa), it could damage the heater through
lack of circulation. If for any reason, the water is
turned off temporarily, to service the equipment for
example, airlock could be a problem when the heater
is turned back on. To eliminate the airlock, open the
pressure relief valve (see Figure 23) and allow the air
to bleed out until water starts to ow. As soon as full
circulation is restored, the trapped air will be released
through the hot water faucets.
Figure 23. Pressure relief valve.
Flow
Switch
Pressure
Relief Valve
High-Limit
Dry Well