10 I Installation
Two temperature and pressure relief valves are supplied and
must be installed in the tank ports marked for this purpose.
No valve or accessory of any type should be installed between
the relief valve and the tank. Please observe local codes for the
correct installation of relief valves.
WARNING:
The pressure rating of the relief valve must
not exceed 850 kPa, the maximum working
pressure of the water heater as marked on the
rating plate.
WARNING:
Relief valve easing gear should be operated
AT LEAST ONCE EVERY SIX MONTHS. If water
does not discharge freely when the lever is
operated, the valve should be checked by an
authorised agent.
WARNING:
The relief valve and relief drain pipe must not
be sealed or blocked. Small amounts of water
may leak from relief valve during heating cycles.
WARNING:
Relief valves should be checked every six
months, or replaced at intervals not exceeding
3 years or more frequently in areas where there
is a high incidence of water deposits.
WARNING:
The function of the temperature and pressure
relief valve installed on this water heater is
to discharge high temperature water under
certain conditions. Therefore it is strongly
recommended that the pipe work connected
to the relief valve is able to withstand water
temperatures exceeding 99
o
C. Failure to follow
this recommendation may result in a dangerous
situation.
The combined kW rating of the relief valves must be 92 kW to
ensure that they are always above the maximum output power
of the water heater when operating. The supplied PTR valves
comply with this.
WARNING:
Never block or seal the outlet of the PTR valve
or its drain for any reason. The warranty will be
void if the relief valves or other safety devices
are tampered with, or if the installation is not in
accordance with this manual.
Connect the outlet of the relief valve to a suitable open drain so
that the discharge water cannot contact any electrical parts,
persons, or animals, and to eliminate any other possible risks.
A drain line from a relief valve must comply with the
requirements of AS/NZS 3500.4.
Always use a valve of the same rated pressure and temperature
as the PTR valves supplied with the unit.
4.2.2 Temperature mixing device (not supplied with the
appliance)
WARNING:
This water heater can heat water to
temperatures which can cause scalding.
Bosch recommends the installation of a temperature limiting
device between the water heater and the hot water outlets in a
bathroom or similar usage point, in order to reduce the risk of
scalding.
Additionally, a certified plumber may have the legal obligation
to ensure the water heater installation meets the hot water
delivery requirements listed in AS/NZS 3500.4.
4.2.3 Pressure limiting valve
(not supplied with the appliance)
In installations where the mains water supply pressure exceeds
that specified for this product, an approved pressure limiting
valve is required and must be fitted.
4.2.4 Expansion control valve
(not supplied with the appliance)
For local regulations, a saturation index greater than +0.4, or
in corrosive water areas where there are sufficient quantities
of silica dissolved in the water the installation of an expansion
control valve (ECV) in the cold water line may be required, being
the last valve installed prior to the water heater.
