Navien Error Code E811: Abnormal circulator operation (inoperable)

How to Fix Navien Code E811

1. Step 1: Turn the unit off and then back on again. This may reset the system and clear a temporary error.
2. Step 2: Check the inlet water valve is fully open. Ensure there is adequate water supply to the unit.
3. Step 3: If the error persists after these steps, contact a qualified HVAC technician to diagnose and repair the issue.

How to Reset Navien Code E811

1. Turn off the unit using the power button on the front panel.
2. Turn off the gas supply valve.
3. Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
4. Restore power at the breaker, then open the gas valve.
5. Turn the unit back on. If the error returns, the underlying issue needs repair.

Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.

What Does Navien Error Code E811 Mean?

The E811 error code on your Navien tankless water heater indicates a problem with the circulation pump, which is responsible for moving water through the heat exchanger. The unit's control board isn't detecting the pump operating as expected. This could be due to a pump failure, blockage in the plumbing, or an electrical issue preventing the pump from running. Without proper water circulation, the unit can overheat, leading to potential damage and a complete shutdown. This error prevents the heater from operating until the problem is resolved.

Common Causes

• Failed or failing circulation pump
• Air trapped in the pump or plumbing
• Blockage in the water lines restricting flow to the pump
• Electrical issue preventing power from reaching the pump (wiring, control board)
• Pump impeller is jammed or broken

Diagnostic Steps

Replacement Parts

Related Codes on Same Models

Other codes that affect the same Navien model families as E811.