Piping Installation; Closed System /Thermal Expansion; Relief Valves - Bosch TRONIC 5000T ES30M Installation Manual

7.4 Piping Installation

Water supply pressure should not exceed 80% of the working pressure of the water
heater. The working pressure is stated on the water heaters' data plate. If this
occurs, a pressure limiting valve with a by-pass may need to be installed in the
cold water inlet line. This should be placed on the supply to the entire building in
order to maintain equal hot and cold water pressures.
Heat cannot be applied to the water fi ttings on the water heater as they
may contain nonmetallic parts. If solder connections are used, solder
the pipe to the adapter before attaching the adapter to the hot and cold
water fi ttings.
Always ensure that all fi ttings are free from leaks.

7.5 Closed System /Thermal Expansion

Periodic discharge of the temperature and pressure relief valve may be due to
thermal expansion in a closed water supply system. The water utility supply
meter may contain a check valve, backfl ow preventer or water pressure reducing
valve. This will create a closed water system. During the heating cycle of the water
heater, the water expands causing increased pressure inside the water heater.
The temperature and pressure relief valve may discharge hot water under these
conditions which results in water escaping from the valve and a build-up of lime on
the relief valve seat. To prevent this from happening, it is recommended to:
1. Install a diaphragm-type expansion tank that is suitable for potable water
on the cold water supply line. The expansion tank must have a minimum
capacity of 1.5 US gallons for every 50 gallons of stored water.
NOTICE: PRODUCT DAMAGE, PROPERTY DAMAGE
 Do not attempt to operate this water heater with the cold
water shut off valve closed.This can result in serious damage
to the water heater tank.
Bosch Tronic 5000T Electric Water Heaters- BTC 724001301 A (10.2021)

7.6 Relief Valves

WARNING:
 The pressure rating of the relief valve must not exceed 150
PSI, and not exceed the maximum working pressure of the
water heater as marked on the rating plate.
WARNING: PERSONAL INJURY, PROPERTY DAMAGE
 Failure to install a listed, adequately sized temperature &
pressure relief valve will release the manufacturer from any
claim which might result from excessive temperatures and
pressures.
To reduce the risk of excessive pressures and temperatures in this water heater,
install temperature and pressure protective equipment required by local codes
and no less than a combination temperature and pressure relief valve certifi ed
by a nationally recognized testing laboratory that maintains periodic inspection
of production of listed equipment or materials, as meets the requirements for
Relief Valves and Automatic Gas Shut-off Devices for Hot Water Supply Systems,
ANSI Z2 I .22. This valve must be marked with a maximum set pressure not to
exceed the marked maximum working pressure of the water heater. Install the
valve into opening provided and marked for this purpose on the water heater, and
orient it or provide tubing so that discharge from the valve is 6 inches above, or
at any distance below, the structural fl oor, and does not contact any live electrical
part. The discharge opening must not be blocked or reduced in size under any
circumstances.
Your local jurisdictional authority, while mandating the use of a temperature-
pressure relief valve complying with ANSI Z2 I .22•CSA 4.4 and ASME, may require
a valve model diff erent from the one furnished with the water heater.
Compliance with such local requirements must be satisfi ed by the installer or end
user of the water heater with a locally prescribed temperature-pressure relief valve
installed in the designated opening on the water heater in place of the factory
furnished valve.
For safe operation of the water heater, the relief valve must not be removed from it
designated opening or plugged.
As an option the T&P relief valve could be placed at it's designated opening on the
top of the water heater (Refer to Part reference illustration).
If other components within the system have a lower working pressure, the relief
pressure rating should be selected accordingly. The BTU rating of the valve must
not be less than the input rating of the water heater.
Only a new temperature and pressure relief valve should be used with this water
heater. Do not use an old or existing valve as it may not be adequate for the working
pressure of the new water heater.
Piping used should be of a type approved for hot water distribution. The discharge
line must be no smaller than the outlet of the valve and must pitch downward from
the valve to allow complete drainage (by gravity) of the relief valve and discharge
line. The end of the discharge line should not be threaded or concealed and should
be protected from freezing. No valve of any type, restriction or reducer coupling
should be installed in the discharge line.
Excessive length, over 30 feet, or use of more than four elbows can cause
restriction and reduce the discharge capacity of the valve.
Installation Manual
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