515Error - Navien NCB-24LSWE Service Manual

5.2.19 515Error

Error occurrence conditions and check items
Error
If an error occurs in the internal circuit of the PCB (e.g., resistance, transistor or relay fault), the system
E515 error
displays 515E (cleared manually) on the PCB.
1. Defective PCB
2. Check with a multimeter if the PCB is supplied with the proper voltage (AC 230 V).
Check items
3. Check the wire connection.
4. Disconnect the ground wire, then check the PCB
Check method
Fault Possible Causes
Defective PCB
Power supply error
PCB or Electrical
supply
Power supply
grounding noise
Version 1.0
Description
Replace the PCB if there is an error with the PCB internal circuit.
Check with a multi-meter if the PCB is supplied with the proper voltage.
 Check with a multi-meter if the voltage at the electrical outlet is AC 230 V.
Power supply grounding noise causes malfunction.
 Disconnect ground from the grounding terminal inside the unit, and check if
the PCB is operating normally.
Check method
NCB Service Manual 115