Safety
Safety devices
19
pump failure. The minimum pressure in the cold water
pipe must be 2 bar and the temperature must not
exceed 15 °C.
Fig. 6-2: Thermal emergency cooling valve
Both thermal emergency cooling valves must be
installed in the cold water supply pipe, so that the
boiler's safety heat exchangers are not continually
under pressure.
Only
thermal emergency cooling valves
that
correspond to the standard DIN EN 14597 (or
comparable standards) may be installed. They must
activate at 100 °C and have a flow rate of at least
2.0 m³/h. The clear width of the cold water supply and
outlet may not fall below the nominal diameter of the
safety heat exchanger.
To prevent the cold water supply from being inadver-
tently shut off, remove the levers from the ball valves
or the hand wheels from the valves and attach them to
the fitting with a piece of wire.
WARNING!
The outlet from the thermal emergency cooling valve
must be directed to the sewer via an easily visible,
open flow path (siphon funnel), so that malfunctions -
especially a non-closing valve - can be recognised.
Fig. 6-3: Connections for thermal emergency cooling valve
on the heat exchanger
The connection for the temperature sensor of the
thermal emergency cooling valve is situated behind
the cover in the panel.
Fig. 6-4: Connection for temperature sensor of the thermal
emergency cooling valve on the heat exchanger
A separate thermal emergency cooling valve must be
installed for the combustion chamber. The connection
for the temperature sensor of the thermal emergency
cooling valve is situated next to the connection for the
safety heat exchanger.
Fig. 6-5: Connections for thermal emergency cooling valve of
the combustion chamber
CAUTION!
In order to measure the correct temperature, the
temperature sensors for the two thermal emergency
cooling valves must be fully inserted into the
immersion sleeves.