515Error - Navien NCB-180 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 displays
E515 error
515E (cleared manually) on the PCB.
1. Defective PCB
2. Check with a multimeter if the PCB is supplied with the proper voltage (AC 102~132 V).
Check items
3. Check the wire connection.
4. Disconnect the ground wire, then check the PCB
Check the sub code
number of E515
Number 1,2 or 10
1. Check the wire connection
between gas controller and
Main PCB.
Check the coil of solenoid
2.
valve.(Refer to page 67)
1. Turn off and on the Power
RESET switch.
2. In that same case, replace the
Main PCB.
Check method
Fault Possible Causes
Defective PCB
Power supply error
PCB or Electrical
supply
Power supply
grounding noise
114 NCB Service Manual
Number 3 or 4
Check the Fan voltage.
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

102~132 V.
Power supply grounding noise causes malfunction.
Disconnect ground from the grounding terminal inside the unit, and check

if the PCB is operating normally.
Description
Number 9
1. Check the wire connection
between dual venturi and
Main controller.
2. Check the dual venturi.
Check method
Number 11 or 12
Version 1.0