Navien CH-180 Service manual - page 61
59
5.3. 02Error
Error conditions and check items
Error
02E
Low water
level
Check items
Description
If the water pressure sensor senses low water level as the heating pipe
pressure is low, the system stops operation of the boiler, and refills water
automatically. As water is filled to the normal water pressure, the system
automatically cancels error, operates the pump for 15 seconds, and returns
the system to the previous state.
When water is filled for the first time after the power is connected, the system
operates the pump in the hot water mode.
The system refills water if water level of 7.3 PSI or lower is detected for over 4
seconds.
The system stops filling water at the water level 12 PSI (the value is depending
on the set-ting).
Filling is stopped forcefully if the water level is 7.4 PSI or higher after 3 minutes
from starting of water refilling.
1. Defective pressure sensor
2. Defective pressure display
1. Water is not refilled.
Check if the cold water valve is closed or frozen.
Check if the auto feeder valve works normally.
2. Water overflows through condensed water hose.
Check the left drain valve of the main heat exchanger.
Check if water leaks due to a defective heat exchanger.
3. Check if water leaks from the heating pipe.
Leaking in unit?
No
Yes
Auto feeder valve Open?
Check in unit (Leaking?)
No
Normal state
Normal Pressure?
Yes
Yes
Check the Auto feeder v/v
Check DHW cold water
Pressure
No
©Navien America Inc. 2010
CH series service Manual
Version 1.0