Heater shows F13; unit may not recognize water flow direction or inlet/outlet configuration.

Safety first: Turn off power and pump before working on plumbing or manifold sensors.

• Verify plumbing: Confirm that the pool water inlet and outlet are connected to the correct ports on the Nirvana reversible water manifold as labeled.
• Check manifold orientation: Some Nirvana heaters allow left/right water connections by rotating the manifold. Ensure the manifold is installed in a supported orientation and that any orientation jumper or plug is set correctly.
• Inspect sensor: Locate the flow direction or manifold sensor on the manifold. Check wiring and connector seating.
• Reset configuration: In the service menu, verify the heater is configured for the actual plumbing orientation. Reset to factory defaults if necessary.
• Replace sensor if needed: If wiring and configuration are correct but F13 persists, replace the manifold sensor with an OEM Nirvana part.