Warning: Your Navien boiler has detected an issue with the inlet thermistor and has shut down to prevent damage. Call a professional for repair.
How to Fix Navien Code E031
Check if the boiler's power is turned off at the main circuit breaker
Inspect the wiring harness and connections for any visible damage or corrosion
Contact a licensed HVAC technician for a thorough inspection and repair
How to Reset Navien Code E031
Turn off the unit using the power button on the front panel.
Turn off the gas supply valve.
Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
Restore power at the breaker, then open the gas valve.
Turn the unit back on. If the error returns, the underlying issue needs repair.
What does E031 mean?
The E031 error on your Navien boiler indicates an open or short circuit in the inlet thermistor. This component measures the temperature of the water entering your boiler. When it's not functioning correctly, your boiler can't accurately monitor the water temperature, leading to system lockouts. This error is common in Navien boilers due to their advanced temperature control systems.
This error occurs when the overheat controller on the burner is initiated during combustion due to the burner overheating. ● If the furnace is continuously inoperable, contact Technical Support at 1-800-519-8794.