Navien NCB-24LSWE, Service Manual

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NCB Service Manual 103 Version 1.0
5.2.11 Error 110
Error Conditions and Checklist
Error Description
E110
Air pressure error
The system detects the air pressure and the fan speed and displays 110E on the front panel in the
following cases:
1. When the initial fan auto-adjustment is not performed.
2. When boiler reaches 95% of maximum heating capacity during combustion and the APS is not rated
at the standard value.
Checklist
1. Check the venturi (burner) hole for obstruction.
2. Check the condensation drain line and drain for obstruction.
3. Check the flue and exhaust are installed correctly and have adequate clearance. (The circulation of
exhaust gas generates noise.)
4. Check if the air supply/exhaust flue is obstructed (rainwater may accumulate inside incorrectly
installed air supply/exhaust pipes).
5. Check for a faulty air pressure sensor or PCB.
6. Ensure that the vents slope downwards towards the unit for proper condensate drainage.
7. Ensure the internal damper moves freely and is not obstructed.