IWAKI EWN -B16 TC, Instruction Manual

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Check valve mounting
Install an optional check valve to the EWN (or a back pressure valve to the FC
type)
for the prevention of a back flow, siphon and overfeeding.
In the following cases be sure to install the check valve.
• A suction side liquid level is higher than a discharge side (See the diagram
below). Or an injection point is below a suction side liquid level at atmospher-
ic pressure.
•
The
elevation difference between two liquid levels is five meters or below,
even if a discharge side liquid level is higher than a suction side.
• A suction side pressure is higher than a discharge side pressure.
• A discharge pressure (including pipe resistance and discharge head) is below
0.13MPa. (0.049MPa for B31 and C36).
Suction side
Discharge side
5m or below
Suction side
Discharge side
Pipework