Q: Why is my pump running but the water flow is very small or has low pressure?

Step 1: Check Motor Direction (Three-Phase Only). If your pump is three-phase, it may be spinning backward. Access the "AC Output Direction" setting by entering the System Operational settings with password 9580. Select "Reverse" to test if the flow and pressure improve. If they do, you should physically exchange any two of the U, V, and W wires at the terminal and then set the software back to "Forward" to avoid future confusion.
Step 2: Check for Jammed Components. If direction is correct, the pump head or motor may be jammed by debris. Pull the pump out of the water and remove the two screws holding the power cable cover. Use a 13mm spanner to undo the 4 bolts connecting the pump head to the motor and lift the pump away. Use pliers to turn the impeller shaft; it should spin freely in both directions. Turn the motor shaft by hand; it should turn with smooth, moderate effort and a "clunking" magnetic sensation.