E109 🟡 Repair Required
Navien Error Code E109: Fan Motor Speed Low
⚠️ 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.
What Does Navien Error Code 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.
Common Causes of Navien Code E109
- Worn-out fan motor
- Faulty control board
- Clogged or dirty fan
- Loose or damaged wiring
Applicable Navien Models
Source Documentation
This error code is documented in 6 official Navien technical manuals.
NFB-H Installation & Operation ManualPage 116
ReasonAbnormal Fan Motor
ActionCheck fan and venting.
Navien NCB-H Installation & Operation ManualPage 129
ReasonAbnormal Fan Motor
ActionClean the intake air filter.
Navien NFB-H Installation & Operation ManualPage 116
ReasonAbnormal Fan Motor
ActionCheck fan and venting.
Navien NFC-H Installation & Operation ManualPage 127
ReasonAbnormal operation: fan motor
ActionManual RESET
Navien NHB-H Installation & Operation ManualPage 119
ReasonAbnormal Fan Motor
ActionCheck fan and venting.
Navien NPF Installation & Operation ManualPage 126
ReasonAbnormal inducer fan operation
ActionThis 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.
Need a Pro to Fix Navien Code E109?
A licensed HVAC technician can diagnose and fix this issue quickly.
Find a Licensed Tech Near You →Replacement Parts for Navien Tankless Water Heater Code E109
Fan Motor Assembly OEM: 9110110000
Control Board OEM: 9110120000