Navien CH-180 Service manual - page 104
102
Error occurrence conditions and check items
5.23. 30Error
Check method
Error
Description
If the system senses the signal continuously for 1 second from the exhaust high
limit switch installed at the top of the exhaust duct when the boiler burns/stopped,
the system displays the 30E (automatically cancelled) heat exchanger exhaust high
limit switch message on the remote controller.
The boiler switches into Lock-Out, and performs post-purge continuously.
Exhaust high limit switch operating temperature: 149
ı (65ç)
30E
Exhaust
high limit
error
Check
items
1. Check if the exhaust high limit switch operates normally.
2. Check if the switch works properly.
Error
type
Possible
Causes
Check method
Remark
Abnormal
sensor
Abnormal the
exhaust high
limit switch
Defective
PCB
Other
trouble
If the trouble continues despite the checking of above items,
replace the PCB.
Abnormal contact point of the exhaust high limit switch 149
ı
(65
ç).
Remove the switch and check, with a multitester, the
resistance (MΩ defect).
©Navien America Inc. 2010
CH series service Manual
Version 1.0