Closed System Thermal Expansion; Electrical Connections - Bosch Tronic 3000T Installation Manual And Operating Instructions

Vertical installation
If you wish to install the unit vertically, with the piping
connections on top:
▶ Install supplied brass plug into tap on side of water heater.
▶ The supplied Temperature and Pressure Relief Valve will
need to be installed on top. See location of T&P relief valve
in Fig. 5 and Fig. 6.
Caution
CAUTION:
To reduce the risk of excessive pressures and temperatures
in this water heater:
▶ Install the supplied temperature and pressure protective
equipment required by local codes but not less than a
combination temperature and pressure relief valve
certified by a nationally recognized testing laboratory that
maintains periodic inspection of production of listed
equipment or materials, as meeting the requirements for
Relief Valves and Automatic Gas Shut-off Devices for Hot
Water Supply Systems, ANSIZ21.22.
The supplied temperature and pressure relief valve is marked
with a maximum set pressure (150 psi) that does not exceed
the marked maximum working pressure of the water heater.
▶ Install the valve in the opening provided and marked for this
purpose in the water heater.
▶ Orient it or provide tubing so that any discharge from the
valve will exit within 6 inches above, or at any distance
below, the structural floor, and cannot contact any live
electrical part. The discharge opening must not be blocked
or reduced in size under any circumstances.
National Plumbing codes may require a drain pan for the water
heater installation. Failure to install one is the sole
responsibility of owner and/ or installer. Reference UPC
(Uniform Plumbing Code), or IPC (International Plumbing
Code).
3.5

Closed system thermal expansion

Periodic discharge of the temperature and pressure relief valve
or failure of the element gasket may be due to thermal
expansion in a closed water supply system. The water utility
supply meter may contain a checkvalve, backflow preventer or
water pressure reducing valve which will create a closed water
system.
During the heating cycle of the water heater, the water expands
causing pressure inside the water heater to increase. The
temperature and pressure relief valve may discharge hot water
under these conditions which results in a loss of energy and a
Tronic 3000T – 6 720 801 072 (2022/07)
build-up of lime on the relief valve seat.
To prevent this from happening, there are two
recommendations:
1. Install a diaphragm-type expansion tank that is suitable for
potable water on the cold water supply line. A minimum 0.5
gallon expansion tank should be used.
Contact the local water supplier or plumbing inspector for
information on how to control this situation. Do not plug the
temperature and pressure relief valve.
3.6

Electrical connections

The ES8 model must be hard wired. As per the National Electric
Code the ES8 needs to be wired with 12 GA. wire to a 20 amp
branch circuit.
Do not use surge protectors or multi-outlet adapters with this
water heater.
▶ Unscrew the junction box cover and remove it.
▶ Insert 12 AWG through conduit into junction box and
secure with conduit strain relief (not supplied).
▶ Connect the wires and screw on the cover of the junction
box.
▶ Make appropriate wiring connections to the water heater
per the National Electric Code.
The unit must be grounded with supplied grounding cable
inside junction box.
▶ Secure junction box cover once wiring connections have
been made.
When the ES8 is not within sight of the electrical circuit
breakers, a circuit breaker lockout or additional local means of
disconnection for all non grounded conductors must be
provided that is within sight of the appliance. [REF NEC
422.31].
Installation instructions
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