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Boiler installation without a reliable device to discharge the excessive
thermal power is forbidden.
2.7.3. Thermal protection
THERMAL PROTECTION
Applications:
5067 thermal protection is designed to protect solid fuel boilers in heating installations fitted with thermostatic valves conforming to the PN-EN303-5
Polish Standard. It is particularly recommended for boilers, which are not equipped with cooling exchanger. Figure 1 presents installation principle, at a
close distance from the boiler, with special consideration for such guiding and sizing of pipes so that no pressure losses occur.
Installation and operating principle: The 5067 thermal protection valve consists of the following elements: non-return valve (1), pressure reducer (2),
thermally-controlled filling valve (3) and ejection valve (4), pressure sensor with a capillary tube(5).
The pressure reduction valve (2) is connected to the water pipe network. The output of the thermally-controlled filling valve (3) is connected to boiler’s
return line. The supply line to the input of thermally controlled ejection valve (4), which output side leads to the outlet. The pressure sensor is installed
in the warmest part, optimally in the upper part of the boiler. The pressure reduction valve is firmly set to 1.2 bar, thus the operating pressure in the
heating device shall be by 0.2 to 0.3 bar higher. This prevents opening of the safety valve in the installation. It is recommended to use a safety valve
with settings of at least 2 bars.
If the preset opening temperature of ca. 90
O
C is exceeded, the filling valve (3) starts to open. In order to maintain stable pressure in the heating
installation, the ejection valve opens at 97
O
C. After the ejection valve opens, hot water flows out of the installation and cold water may flow in from the
supply line, this cools down the boiler. When boiler temperature drops to 94
O
C, the ejection valve closes. Thermally controlled filling valve and
temperature sensor help to restore the correct flow pressure in the heating installation.
When the temperature reaches 88°C, also the filling valve closes.
Build:
The thermal protecting device is controlled by two independent valves: the filling valve and the ejection valve. The body of the device is a die stamped
brass element whilst other parts that contact water are made of stainless steel and temperature resistant plastic. All sealing elements are made of resilient
and high-temperature resistant, heavy duty elastomeric rubber material. Springs are made of stainless spring steel. The sensor and capillary tube are
made of copper, whereas the sleeve is additionally nickel-plated.
Valve opening is controlled by doubled temperature sensor. The fittings are self-venting. Elements of the valve, the valve seat and seal may be removed
and cleaned without any change to pre-set opening temperature. Compact head of the temperature sensor may be conveniently disassembled during the
valve body installation. The capillary tube from the sensor to actuator is protected by a special, metal flexible hose.
Pressure reducer operating pressure:
Maximum water inlet pressure:
Minimum required inlet water pressure :
Temperature
filling valve
ejection valve
Maximum operating temperature
Capillary tube
Weight
1.2 bar (factory-fixed)
16 bar
2.3 bar
of opening::
of closing:
90°C +0/-2°C
88°C +0/-2°C
97°C +0/-2°C
94°C +0/-2°C
135°C
1300 mm – standard length
1.5kg
dimensions in mm unless otherwise stated
