Warning: Your Navien boiler's fan motor is running slower than normal, which could lead to system issues. It's safe to troubleshoot, but call a pro if needed.
How to Fix Navien Code E109
Check if the fan is making unusual noises. If it's loud or grinding, it might need professional attention.
Turn off the boiler and check the fan blades for dirt or debris. Clean them gently with a soft brush if you can, but don't force anything.
If the fan seems clean and quiet, and you're comfortable doing so, check the wiring connections. Tighten any loose screws, but don't force them.
How to Reset Navien Code E109
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 E109 mean?
The E109 error on your Navien boiler indicates that the fan motor speed is lower than it should be. This could be due to a problem with the motor itself, or an issue with the control board that's regulating its speed. The fan helps to circulate air around the heat exchanger, so if it's not working properly, your boiler might not heat your home as efficiently as it should.
This error occurs when the fan’s RPM is abnormal. ● Turn off the furnace, turn it on again and check if the furnace operates properly. ● If the furnace is continuously inoperable, contact Technical Support at 1-800-519-8794.