594Error - Navien NPE-180A Service Manual

5.1.22 594Error

Error occurrence conditions and check items
Error
E594 error If the communication is abnormal in parts of PCB, the system displays E594 on the PCB.
Check items 1. Check the PCB.
Check method
Fault Possible Causes
E594 Error communication by
5.1.23 615Error
Error occurrence conditions and check items
Error
E615 error Abnormal signal input by PCB.
1. Turn the POWER RESET switch OFF then ON (or unplug and replug the power supply.
Check items
2. If the system still displays E615, replace the main PCB.
1. Click the Reset button on Front panel.
Abnormal
2. Turn the POWER to the unit OFF then ON. Disconnect then reconnect power if
necessary.
PCB.
3. If the system still displays E594, replace the main PCB.
Description
Check method
Description
Troubleshooting 115