Two-pipe heating system
Example of calculation:
Solution to:
- level of valve setting
Given:
- heat output: Q = 1135 W
- cooling of water: t1 - t2 = 15 K (65/50 °C)
- pressure loss of radiator with valve: Δp = 30 mbar
- heat capacity of water: c = 1,163 Wh/kg.K
Solution:
- mass flow:
| m = | Q c . (t1 - t2) | = | 1135 1,163 . 15 | = 65 kg/h |
Level of valve setting (see diagram): 4
| Radiators in version VENTIL KOMPAKT without connecting fittings | Level of valve setting | Highest allowed working temperature [°C] | Highest allowed working pressure [bar] | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | |||||
| Valve with eight levels of setting and with a thermostatic head | kV [m3/h] | 0,13 | 0,22 | 0,31 | 0,38 | 0,47 | 0,57 | 0,66 | 0,75 | 110 | 10 | |
| kVS [m3/h] | 0,16 | 0,27 | 0,38 | 0,43 | 0,65 | 0,98 | 1,23 | 1,43 | ||||
| The indicated values of kv comply with proportionality interval of 2 K. | ||||||||||||
Conversion table for valve setting
Setting of 8-level valve following a calculation made for a 6-level valve.
| Level of valve setting | ||||||
|---|---|---|---|---|---|---|
| 6-level valve | 1 | 2 | 3 | 4 | 5 | 6 |
| 8-level valve | 1 | 1 | 2,5 | 4,5 | 6,5 | 8 |