Pentair SuperFlo VS Fault 0F — AC Under Voltage
Fault 0F (also displayed as "OF") on the SuperFlo VS means the supply voltage has dropped below the pump's 99V minimum operating threshold. The pump stops to protect the drive electronics from damage caused by running on insufficient voltage.
This fault may self-clear if caused by a temporary utility voltage dip. If it recurs, there is a supply or wiring problem that requires investigation.
What Causes Fault 0F?
Utility Voltage Variation
Brief voltage sags from the utility grid are the most common cause of a one-time 0F fault. These typically self-resolve when the grid voltage recovers.
Installation Problems
- Undersized wire gauge: Too-small wire for the run length causes voltage drop under load
- Loose connections: Loose terminal block connections at the pump or panel create resistance and voltage drop
- Corroded connections: Corrosion on terminals adds resistance
- Long wire run: Excessive distance from panel to pump without proper wire sizing
Other Causes
- Generator power with voltage inconsistency
- Other high-draw equipment on the same circuit
- Panel issues (tripped leg, failing breaker)
Troubleshooting Steps
Step 1: Power Cycle
- Turn off breaker
- Wait until all keypad LEDs turn off
- Turn breaker back on and restart
- If fault 0F does not return, monitor for recurrence
Step 2: Measure Supply Voltage
- Use a multimeter to measure voltage at the motor's terminal block while the pump is running
- The SuperFlo VS accepts 99–253V — it runs on both 115V and 230V without rewiring
- Voltage should be within 10% of the nominal supply: 103–127V (115V systems) or 207–253V (230V systems)
- Also measure voltage at the breaker panel — compare readings to identify voltage drop in the wire run
Step 3: Check Wire Connections
- Turn off breaker — wait for LEDs to go out
- Open the field wiring compartment (1/2" NPT conduit port on the drive)
- Inspect all terminal connections for tightness
- Look for discoloration (heat damage from loose connections), corrosion, or insulation damage
- Tighten any loose terminals
Step 4: Verify Wire Gauge
Wire must be sized per the National Electrical Code for the circuit ampacity and run length. The SuperFlo VS draws up to 13.2A (115V) or 12A (230V). Consult a licensed electrician if wire sizing is in question — undersized wire cannot be field-corrected without rewiring.
Step 5: Isolate the Circuit
The pump should be on a dedicated circuit with no other loads. Lights, automation systems, or other equipment sharing the circuit can cause voltage sag when they operate simultaneously.
Voltage Operating Range
| Parameter | Value |
|---|---|
| Minimum operating voltage | 99V |
| Maximum operating voltage | 253V |
| Frequency | 50 or 60 Hz |
| Maximum current (115V) | 13.2A |
| Maximum current (230V) | 12.0–11.5A |
When to Call an Electrician
- Voltage consistently measures below 103V (115V systems) or 207V (230V systems)
- Voltage at panel is normal but voltage at pump is significantly lower
- Connections show heat damage or corrosion
- Fault 0F recurs after checking connections