441Error - Navien NFC-175 Service Manual

5.2.25 441Error

Error Condition and Check Items
Error
E441
Check Items
110 NFC Service Manual
Hot water outlet 2 (before mixing valve)
1. Check for disconnections in controller harness
Check for disconnection in the harness between hot water outlet 2 temperature sensor
●
and the controller.
2. Change hot water outlet 2 temperature sensor
If the problem persists after completing close external water supply valve and purge
●
water pipes of residual water. Change hot water outlet 2 temperature sensor.
3. Change PCB
If the problem persists after completing all the actions above, change the PCB.
●
Description
Hot water outlet
2 temperature
sensor
Version 1.0