Afriso EURO-INDEX PrimoTherm 180-1 DN25 Notice Technique page 57

5.3 Determining the Kvs flow coefficient value
The adjustment value for the flow efficient Kvs of the orifice is determined on
the basis of the power of the heating circuit (KW) and the temperature spread
between flow and return (K corresponds to °C); refer to the following table.
Example:
A. Capacity: 20 KW
B. Temperature spread: 20 K -> 20 °C
C. Point of intersection in the centre of the optimum range 3-15 kPa
D. Read adjustment value: 3 (in m³/h at a differential pressure of 1 bar)
Mounting
A
B
C
PrimoTherm® DN25
EN
D
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