INSTALLATION, OPERATION AND MAINTENANCE MANUAL
Bisolid Automat OM-BAV05/02/2018/EN
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The two-way safety valve DBV 1 is used for protecting boilers against overheats. Outlet and
inlet valves are integrated in the valve body operated by a thermostatic element. Upon
reaching the limit temperature, the outlet and inlet valves open simultaneously allowing for
cold water to start flowing into the boiler and hot water to start discharging out of the boiler.
Upon lowering the temperature to a level below the limit value, the outlet and inlet valves close
simultaneously.
Figure 23. Two-way safety valve DBV 1
A - Cold water inlet.
B - Outlet to the boiler.
C - Draining outlet - pipeline.
D - Inlet from the boiler.
In the event of activation of the two-way safety valve that might cause inflow
of water, not meeting the requirements set out in Table 18, the water in
the system should be treated as per the requirements. Furthermore,
the pressure in the heating system should be adjusted to the desired value.
The two-way safety valve does not replace the safety valve.
If the pressure in the water pipeline is higher than 6 bar, a reducing valve should be installed
on the cooling water inlet. It should also be installed when after an additional cooling the
pressure in the heating system is too high. In these cases, it is recommended that the
pressure of the reducing valve is adjusted at a value twice the value of the pressure necessary
for the heating system, and the minimum is 2 bar.
9.5.3. INSTALLATION OF THE TWO-WAY SAFETY VALVE
The installation of the two-way safety valve should be performed only by
a qualified person. For optimum operation of the thermostatic two-way safety
valve, it is necessary to comply with the prescribed conditions for installation
and to observe the flows direction indications marked on the valve body.
