and its operation is complete mechanic without electric or spare parts. After the
decrease of boiler temperature under a limit the valve closes again and the water
stops to come into the serpentine.
If the web pressure is over 6 bar it is necessary to install a pressure reducer before
the installation. Noted that this valve does not replace the safety valve and it is
important to install safety valves too (at least 2).
Temperature and pressure relief valve
The T&P valve has a temperature sensor and provides double safety against
temperature (90
o
C) and pressure (3 bar). The output of the valve should be
connected with the drain for the disposal of the overheated water. The T&P valve
should be connected nearby to the boiler and necessary at the outlet. It provides
safety in case of closed type expansion tank installation but it is not replace the
overheating safety system.
Technical data:
Temperature (limit)
90
ο
C
Pressure (limit)
3 bar
Connection
½”
Discharge rating:
10 kW
Dimensions
A
B
C
D
E
F
½”
Ø15
40
102
88
39
4.5. Thermal protection of the boiler
The boiler should be operated within the supply and return water temperature
differences in the range of 10
–
15°C.
Because of the lifecycle of the boiler, it should be operated with the return
water temperature not
lower than 60°C.
In practice, it is difficult to meet this condition because the average
atmospheric conditions during the entire heating season “require” lower
settings.
