7 Function of the check valves [specialist]
30
EN-XXX_CIRCOtransfer-30E-50E_TI-MA-BA-150401-3PAW0501 - 99609x7WAG0x-mub-en - V06
2015/03
Do you need to know it exactly?
The density of the solar fluid decreases with rising temperature. In high installations with large
temperature differences, the difference in density will cause gravity circulation.
Calculation example: Δp = Δρ * g * h
Collector temperature: 5 °C
Density solar fluid ρ1 = 1042 kg/m³
Storage tank temperature: 67 °C
Density solar fluid ρ2 = 1002.5 kg/m³
Δρ = ρ
1
-
ρ
2
= 39,5 kg/m³
g = 9,81 m/s²
Installation height h = 10 m
Δp = 3875 Pa = 395 mm wc
The two check valves in the station (2 x 200 mm wc) are sufficient for an installation height
of 10 m and a temperature difference between the collector and the tank of up to 62 K.
