Low Feedback/Water Fault

What does LFB/LW mean?

The iQpump VTC displays a “Low Feedback/Water (LFB/LW)” fault when the feedback level falls below the programmed level (P1-08) for a time specified in P1-09. When this fault occurs, the iQpump VTC will coast to a stop. This function is only active during running while operating in the auto mode.

• System feedback level drops below the threshold set in parameter P1-08 (Low Feedback Level).
• The low feedback condition persists for longer than the delay time specified in parameter P1-09 (Low Feedback Level Fault Delay Time).
• Malfunction of the feedback device (e.g., pressure transducer) providing an incorrect low signal.

Click steps to track your progress.

1. 1

   Verify the actual system feedback level using a calibrated external gauge or sensor.

2. 2

   Check parameter P1-08 (Low Feedback Level) and adjust it to an appropriate minimum allowable feedback value for the application.

3. 3

   Check parameter P1-09 (Low Feedback Level Fault Delay Time) and adjust if the delay is too short for normal system transients.

4. 4

   Inspect the feedback device (e.g., pressure transducer) and its wiring for damage or incorrect calibration; measure its output signal (e.g., 4-20mA or 0-10V) at the iQpump VTC input terminals.