EN 215-2019 pdf download.Thermostatic radiator valves-Requirements and test methods.
6.4.1.3 Characteristic flow rate for thermostatic valves and integrated thermostatic valves with pre-setting
For thermostatic valves and integrated thermostatic valves with pre-setting, plot curve 3 (Figure 13) for each specified presetting position. If there are more than 3 specified pre-setting positions, the test shall be carried out only at the lowest, highest and one pre-setting position selected by the test laboratory.
The flow rate at S-2 K is obtained, This flow rate represents the characteristic flow rate.
6.4.1.4 Maximum flow rate
Measure the flow rate at an Intermediate setting of the temperature selector with the sensor held at 2 °C ± 1 °C and with a differential pressure of 10 kPa (0,1 bar) ± 2 %.
Afterwards compare the largest flow rate obtained on curve 3 (Figure 13) with that as determined above.
The larger of the two is the maximum flow rate.
6.4.1.5 CharacteristIc flow rate at the minimum and maximum setting
Use the method described in 6.2.2. The flow rate at S2 K (qm,s,min and qm,s.max) is obtained from curves 1 and 2 (Figure 13).
6.4.1.6 Sensor temperature at minimum and maximum setting of the temperature selector
The sensor temperatures referring to the flow rates qm,s,min and qm,s,max shall be obtained from curves 1 and 2 (Figure 13).
6.4.1.7 Hysteresis at nominal flow rate
The hysteresis is represented as the difference of the temperatures in Kelvin at a nominal flow rate between the opening and closing curves 3 and 4 in Figure 13 obtained immediately one after the other.
6.4.1.8 DIfferential pressure Influence
The differential pressure influence is represented as the distance between the temperature points S in Kelvin of the theoretical closing curves 4 and 6 in Figure 13.
6.4.1.9 Influence of the static pressure
The influence of the static pressure Is represented as the temperature difference in Kelvin between the closing curves 4 and 7 in Figure 13 for the nominal flow rate.
6.4.1.10 Temperature difference between temperature point S and the closing and opening temperature respectively
Record the difference in Kelvin between the respective temperature points S and the temperature for valve closing (e) and for valve opening (fJ from the characteristic curves as shown in Figure 9.
6.4.1.11 Influence of ambient temperature on thermostatic valves with transmission elements
The influence of the ambient temperature is represented as the temperature difference in Kelvin between the opening curves 3 and 5 in Figure 13 for the nominal flow rate.
6.4.1.12 Water temperature influence
The test shall be carried out in an apparatus as described in 6.1.1 and 6.1.3 without any change of the temperature selector setting.
The air temperature shall be decreased by at least 6 K below the closing temperature. Then, the air temperature shall be increased until the water flow rate through the valve has reached 0,9 to 1,2 times of the nominal flow rate in equilibrium condition. The water flow rate is then measured and recorded on closing curve 4.
Increase the water temperature to at least 70 °C and wait for equilibrium condition. During that time the air temperature shall not drop but may increase by 0,2 K maximum. The water flow rate shall be measured and recorded on closing curve 4 as well (Figure 20).
It shall beat least 0,1 times of the nominal flow rate, otherwise the measurement shall be repeated with smaller water temperature increase.
With the temperature difference between points ‘2 — T1, which can be obtained from the closing curve, and with the air temperature increase ITL, the effect of the water temperature is obtained according to the following formula:
6.4.2 Endurance tests and temperature resistance test
6.4.2.1 Mechanical endurance test
Before this test, plot the curve 3 (Figure 13) and mark the tempelature selector setting. Then, mount the valve in a device supplied with water at 90 °C ± 2 °C and with a static pressure of 100 kPa (1 bar). The differential pressure shall be adjusted to 60 kPa (0,6 bar) ± 2 % at the closed position of the valve. Operate the temperature selector for 5 000 cycles. The time taken for one turn shall be approximately 10 s, and the temperature selector shall not quite touch the mechanical stop. There shall be a waiting period of 5 s at each reversal of rotation. The temperature at the sensor shall be such that complete opening and closing can be achieved.
After the mechanical endurance test the thermostatic valve shall be stored at least 24 h in the open position, at ambient temperature.
After this test, readjust the temperature selector to the marked setting and plot the characteristic curve 3 (Figure 13) again. Establish the nominal flow rate and the sensor temperature at nominal flow rate obtained both before and after the endurance test.
6.4.2.2 Thermal endurance test
Before this test, plot the curve 3 (Figure 13). Do not change the setting of the temperature selector throughout the whole test. Then, mount the valve in a device that permits immersion of the thermostatic head assembly 5 000 times alternately in 2 water baths at temperatures of 15°C ± 1 °C and 25 °C ± 1 °C respectively. The water of the baths shall contain no additives not expressively permitted by the manufacturer. No water shall flow through the valve. The thermostatic head assembly shall remain in each bath for at least 30 s.
Make sure that the thermostatic valve closes completely during its immersion in the water bath at 25 °C and opens at least as far as to obtain the nominal flow rate in the water bath at 15 °C. Otherwise, the time shall be prolonged.EN 215-2019 pdf download.