WALTIS VIVA GT 25, Instructions For Use Manual

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VALTIS OGREVANJE d.o.o.
4
DEVICE INFORMATION Viva
GT
Installation of thermal discharge protection against overheating (STS)
The use of a thermal safety valve is mandatory wherever the boiler is connected to a
closed system and uses solid fuel as an energy source. The valve prevents the temperature
of the water in the boiler from rising above the boiling point at normal air pressure. The
thermal safety valve must be installed close to the hearth with the sensitive element
immersed in the boiler water and the valve with two tubes. The starting temperature is 97 °C
and the outlet temperature is 110 °C. The maximum pressure is 10 bar and the maximum
outlet capacity is 6.5 m3/h. The thermal safety valve is equipped with 2 sensing elements; in
case one sensing element breaks down, the other ensures that the valve works and provides
double safety.
The safety heat exchanger installed in the boiler must be connected by the system
installer to the cold water network in the house via a thermal discharge valve to ensure that
the boiler is protected against overheating in the event of a pump failure. The minimum
pressure in the cold water duct must be 2 bar and must not exceed 15 °C.
Only thermal discharge protection complying with DIN EN 14597 (or comparable
standards) may be installed. These must be triggered at 100 °C and allow a flow rate of at
least 2.0 m³/h. The clear width of the cold water supply and outlet must not be less
than the nominal width of the safety heat exchanger. The cold water supply must be
connected to the upper connection of the safety heat exchanger and the lower connection is
intended as a drain to the duct. To ensure that the supply cannot be closed unintentionally,
the lever or handwheel must be
removed from the ball valves and suspended from the fitting by a piece of wire.
To help identify errors, the outflow requires a flow path that can be monitored. Remove
the water out through a siphon funnel, or at least through a hose, to the floor so that no one
can get scalded when the valve is opened.
1. Cold water connection
2. Check tap, remove handwheel
3. Dirt trap
4. Thermal discharge safety device
5. Visible outflow into the canal
Safety cut-off with STB switch (safety temperature limiter)
As an additional safety against overheating, the boiler is equipped with a safety
temperature limiter (STL) which, in the event that the boiler reaches 100 °C
(temperatures 95 to 105 °C are tolerated), blocks the suction fan so that it can no longer
be switched on. The STL can be manually released when the boiler temperature drops
below 90 °C again, and the boiler can be restarted when the boiler temperature drops
below 70 °C.