Navien NCB-180, Service Manual

Page: 117 / 149

114 NCB Service Manual Version 1.0
5.2.19 515Error
Error occurrence conditions and check items
Error Description
E515 error
If an error occurs in the internal circuit of the PCB (e.g., resistance, transistor or relay fault), the system displays
515E (cleared manually) on the PCB.
Check items
1. Defective PCB
2. Check with a multimeter if the PCB is supplied with the proper voltage (AC 102~132 V).
3. Check the wire connection.
4. Disconnect the ground wire, then check the PCB
Check method
Fault Possible Causes Check method
PCB or Electrical
supply
Defective PCB
Replace the PCB if there is an error with the PCB internal circuit.
Power supply error
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
102~132 V.
Power supply
grounding noise
Power supply grounding noise causes malfunction.

Disconnect ground from the grounding terminal inside the unit, and check
if the PCB is operating normally.
Check the sub code
number of E515
1. Check the wire connection
between gas controller and
Main PCB.
2.
Check the coil of solenoid
valve.(Refer to page 67)
Check the Fan voltage.
1. Check the wire connection
between dual venturi and
Main controller.
2. Check the dual venturi.
Number 3 or 4
Number 1,2 or 10
Number 9
Number 11 or 12
1. Turn off and on the Power
RESET switch.
2. In that same case, replace the
Main PCB.