08Error - Navien CH-180 Service Manual

5.9. 08Error

Error conditions and Symptoms Analysis
Error
08E
Hot Water
Check the hot water temperature sensor. If a problem (short-circuit: 248
outlet
higher) is detected for 3 seconds, the system displays the error message 06E on
thermistor
the indoor thermostat.
short
1. Check if the hot water temperature sensor connector is wet due to any reason,
Check
including leakage.
items
2. Replace the defective hot water temperature sensor.
3. Replace the PCB.
Is the Supply thermistor
normal ?
Yes
Check connector
Check method
Possible
Fault
Causes
Defective
temperature
sensor
Sensor
connector
error
Temperture
sensor
Other
Defective
trouble
PCB
©Navien America Inc. 2010
Description
No Replace Supply thermistor
Resistance between two white wires of CN 13 is from
0.8 to 20k ohm at normal condition.
Caution : Before measuring resistance of the thermistor,
remove the connector from the PCB.
Check method
Check if the hot water temperature sensor connector or the PCB
harness terminal is wet due to any reason, including leakage.
Check the current heating temperature on the display.
Measure the temperature sensor resistance, if the value is 0Ω,
replace the temperature sensor
If the trouble continues despite the checking of above items,
replace the PCB.
74
CH series service Manual
or
Version 1.0