User Manual
Error Code Guide
28
If an error code is constantly displayed on the display window, receive
an inspection by contacting the Navien customer support center in the US.
(877-689-1541).
Error
Code
Error Description Cause Action to Be Taken
Er02 Water shortage error There is a lack of water.
Replenish the water in the
heating unit.
* Water level cannot be read when
distilled water has been used.
Please test the unit with tap water
and if there is no issue, use the
ZDWHUVSHFLȴHGLQWKLVPDQXDO
(Mineral water)
Er05
Water tank supply
temperature sensor
error
There is a disorder in
the supply temperature.
Please contact the
Navien Technical Support.
Er11
Water level detection
Error
Normal water level
detection is dysfunctional.
Please contact the dealer or
Navien Technical Support.
* Water level cannot be read when
distilled water has been used.
Please test the unit with tap water
and if there is no issue, use the
ZDWHUVSHFLȴHGLQWKLVPDQXDO
(Mineral water)
Er16
Water tank overheating
error
The temperature of the
water tank is overheated.
Please contact the dealer or
Navien Technical Support.
Er17 Heating disorder Error
There is a disorder with
a part related to heating.
Please contact the dealer or
Navien Technical Support.
Er18
Return water temperature
sensor error
There is a disorder in
the return water
temperature sensor.
Please contact the dealer or
Navien Technical Support.
Er28 Water leakage error
A water leak caused by a
damaged hose inside
the pad is detected.
Please contact the dealer or
Navien Technical Support.
* Water level cannot be read when
distilled water has been used.
Please test the unit with tap water
and if there is no issue, use the
ZDWHUVSHFLȴHGLQWKLVPDQXDO
(Mineral water)