User Manual

Check Explanation/comment Checked
Check that a check valve is installed in
the discharge line, between the
isolation valve and the pump
discharge outlet.
The location between the isolation valve and the
pump allows inspection of the check valve.
The check valve prevents damage to the pump and
seal due to the back flow through the pump, when
the drive unit is shut off. It is also used to restrain
the liquid flow.
See Example: Discharge piping equipment for
illustrations.
If increasers are used, check that they
are installed between the pump and
the check valve.
See Example: Discharge piping equipment for
illustrations.
If quick-closing valves are installed in
the system, check that cushioning
devices are used.
This protects the pump from surges and water
hammer.
Example: Discharge piping equipment
Correct Incorrect
1
2
3
4
1. Bypass line
2. Shut-off valve
3. Check valve
4. Discharge isolation valve
2
1
1. Check valve (incorrect position)
2. The isolation valve should not be positioned
between the check valve and the pump.
Installation
38 Model 3198 i-FRAME Installation, Operation, and Maintenance Manual