Abnormal air pressure Manual reset
The E110 error code on Navien boilers indicates abnormal air pressure manual reset. Symptoms include the system senses the air volume and the rpm signal, and displays 110e on the front panel in the following, generates noise.), 1. if 110e occurs intermittently during ignition or combustion, compare the.
Navien E110 means: abnormal air pressure manual reset. The usual causes are defective air pressure sensor or pcb, blocked condensate drain or if the air pressure sensor hose is broken or clogged. You can safely reset the boiler once — if E110 returns, do not keep resetting. A qualified heating engineer should diagnose the root cause.
What Does E110 Mean
The E110 code is shown by the boiler’s control board when it detects abnormal air pressure manual reset. The boiler then stops instead of continuing to run in that condition: the code is the appliance reporting a problem, not proof that the boiler is broken.
| What you see on the boiler |
|---|
| The system senses the air volume and the RPM signal, and displays 110E on the front panel in the following |
| generates noise.) |
| 1. If 110E occurs intermittently during ignition or combustion, compare the |
Common Causes
Causes documented in 2 technical sources.
| Cause |
|---|
| Defective air pressure sensor or PCB. |
| Blocked condensate drain |
| If the air pressure sensor hose is broken or clogged. |
| Exhaust air is blocked due to condensate drain error. |
| Defective air |
Safety Warning
E110 involves electrical or pressure-related components. Do not attempt repairs without proper qualifications. Ensure the boiler is electrically isolated before any inspection. If you notice water leaks, unusual sounds, or pressure anomalies, contact a qualified heating engineer immediately.
Parts & Prices
Prices shown are indicative. Actual prices and availability vary by region.
Step-by-Step Diagnosis
Note the original fault code that caused the lockout
Investigate and resolve the underlying cause before resetting
Check the fault history in the boiler's diagnostic menu
Do not repeatedly reset without investigation — repeated lockouts indicate a persistent problem
How to Fix It
Resolve the underlying fault first
reset the boiler by pressing the reset button (typically hold for 3-5 seconds)
if the boiler locks out again within a short period, do not continue resetting — call a qualified engineer
Remove bottom of trap and verify it is not blocked.
Refer to the Navien service documentation for the detailed procedure. Only a qualified engineer should carry out these repairs.
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Affected Models
Navien models that can display fault code E110:
| Model Family | Output Range | Frequency |
|---|---|---|
| All Navien models | — | Possible |
Frequently Asked Questions
Resolve the underlying fault first. According to the technical documentation, this is the first check on the list for E110.
E110 is not classified as a high-severity fault, so the boiler can be reset once. If E110 comes back, stop resetting: the underlying cause is still there and needs a qualified heating engineer.