Pentair IntelliFlo3 VSF Priming Failure Alarm
The priming failure alarm on the Pentair IntelliFlo3 VSF indicates the pump was unable to establish sufficient water flow during the priming sequence. Priming failure can be caused by lack of water in the volute strainer basket.
How Alarms Display on the IntelliFlo3 VSF
The IntelliFlo3 VSF uses a different interface than traditional keypads. When an alarm is triggered, the drive's ON/STOP LED will blink RED and a fault code will display. The pump will stop until the alarm is resolved.
Depending on your particular setup, fault codes will display on one or more of the following user interfaces:
- Pentair Pool app
- Automation system interface
- Optional Touchscreen Controller (Almond — P/N 356159z, Black — P/N 356348z)
What Causes Priming Failure?
According to the manual, priming failure can be caused by lack of water in the volute strainer basket. The troubleshooting chart identifies the following specific causes:
Air Leaks in the Suction Line
- Loose or cracked pump strainer lid
- Worn or missing lid O-ring
- Air pockets or leaks in suction line piping and seals
Insufficient Water
- Pool water level not covering the skimmer opening
- Strainer pot not filled with water before startup
- Suction lines not full of water
Clogged Strainer Basket
A clogged pump strainer basket restricts water flow to the pump and can prevent successful priming. Clean the pump strainer basket per the Cleaning the Pump Strainer Basket procedure in the manual.
Step-by-Step Troubleshooting
Step 1: Check Water Level
Verify the pool water level is sufficient to prevent the skimmer from drawing air. Add water if the level is low.
Step 2: Fill the Strainer Pot
- Turn off power to the pump at the circuit breaker
- Open the filter's air relief valve and stand clear until pressure drops to 0 PSI
- Turn the strainer pot lid counter-clockwise and remove it
- Fill the strainer pot up to the suction port with water
- Place the lid onto the strainer pot and tighten until the lid handles are perpendicular to the suction port
- Ensure the lid O-ring is properly seated and is not being pinched between the lid and strainer pot
- Open all valves in suction and return lines
- Open the filter's air relief valve and stand clear of the filter
- Restore power and press ON/STOP to start the pump
Step 3: Inspect Suction Piping for Air Leaks
Inspect all piping and seals in the suction line. Look for loose fittings, cracked pipe, or worn valve glands. While the pump is running, air bubbles visible in the strainer basket indicate an active leak.
Step 4: Clean the Strainer Basket
A clogged strainer basket is a common cause of priming failure. Clean the basket according to the Cleaning the Pump Strainer Basket section of the manual.
Manual Caution
Do not allow your pump to run longer than 30 minutes without successfully priming. If the pump does not prime, check your priming settings or refer to the Troubleshooting section.
Default Priming Settings
The following are the factory default priming parameters for the IntelliFlo3 VSF. These can be adjusted via the Pentair Pool app, optional touchscreen (Device Settings > Priming Parameters), or automation system interface.
| Setting | Default |
|---|---|
| Priming Mode | Enabled |
| Dry Run Detection | Enabled |
| Priming Speed | 100% |
| Max Priming Duration | 11 minutes |
| Priming Range | 5 |
| Delay | 20 seconds |
| Loss of Prime Detection | Enabled |
Default Schedule
If the pump is started using the ON/STOP button before a customized schedule is programmed, the pump will run the default Program 1 schedule: 24 hours at 30 GPM. Custom programs can be edited via the Pentair Pool app or the optional touchscreen controller.