Pentair IntelliFlo Over Voltage Alarm
The over voltage alarm indicates excessive supply voltage or that an external water source is causing the pump and motor to rotate, generating excessive voltage on the drive's internal DC bus.
The drive will automatically restart 20 seconds after the over voltage condition clears.
Common Causes
Excessive Supply Voltage
- Utility voltage spike
- Nearby equipment causing voltage fluctuations
- Improper transformer tap setting
- Generator supplying inconsistent power
Back-Driving the Motor
When the pump is stopped but water continues to flow through it, the motor acts as a generator:
- Solar heating systems: Thermosiphon effect pushing water through stopped pump
- Elevated spa: Water draining back through pump
- Waterfall/water features: Gravity flow when pump stops
- Multiple pumps: One pump pushing water through another
Troubleshooting Steps
Step 1: Check Supply Voltage
- Measure voltage at the electrical panel
- Measure voltage at motor terminals
- Compare readings - should be 230V +/- 10%
- If consistently high, contact utility company
Step 2: Check for Back-Driving
- Stop the pump
- Observe if impeller continues spinning
- Look for water movement through clear lid
- Listen for flow sounds
Step 3: Install Check Valve
If back-driving is identified:
- Install check valve on discharge side of pump
- Prevents reverse flow when pump stops
- Common solution for solar heating systems
Step 4: Adjust Stop Delay
Use Stop Delay feature to prevent immediate stop:
- Press Menu button
- Navigate to Programs
- Select the program you want to modify
- Set Stop Delay (default is 0 minutes)
- This allows pump to ramp down gradually
Solar Heating Systems
Solar pool heating is a common cause of over voltage due to thermosiphon effect:
- Hot water rises through solar panels
- Creates flow even when pump is off
- This flow rotates the pump impeller
- Motor generates voltage that triggers alarm
Solutions for Solar Systems
- Install check valve between pump and solar panels
- Program pump to run during solar collection hours
- Consider solar controller that coordinates with pump
Multiple Pump Systems
In systems with multiple pumps plumbed together:
- Ensure check valves on each pump's discharge
- Coordinate pump schedules to avoid conflicts
- Verify proper valve configurations
When to Contact Electrician
- Supply voltage consistently above 253V
- Voltage fluctuates wildly
- Other equipment also experiencing issues
- Alarm persists after addressing back-driving