PAW SolexMega-Kaskade HZ, Инструкции по установке и вводу в эксплуатацию

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10 Functioning of the check valves
42 996098460-mub-en – V02 2016/05
10 Functioning of the check valves
Within its application range, the check valve of each cascade module prevents undesirable
gravity circulation.
The efficiency of the check valve depends on:

the installation height

the temperature difference between the storage tank and the collector

the heat transfer fluid used
The diagram below indicates if the check valve integrated in the modules is sufficient for your
installation. If the check valve is not sufficient, additional components must be installed in order
to prevent gravity circulation.
Components such as syphons ("heat traps") or additional check valves can be installed for
this purpose. Make sure that the collector field is not separated from the safety group by the
additional valves.
Example:

Each cascade module is equipped with a check valve (200 mm wc) in the return line.
 You use a mixture of water and 40% of propylene glycol as solar fluid.

The installation height between the collector and the storage tank is 10 m.
Instal
latio
n hei
gh
t i
n
m
Temperature difference collector / storage tank in K
Result:
The check valve prevents gravity circulation up to a temperature difference of about 25 K.
If the temperature difference between the collector and the tank is larger, the difference in
density of the solar fluid will be so large, that the check valve is pushed open.
C i r c u l a t i o n