Way Valve - Navien NCB500-2S/37K Service Manual

4.7.14 3 Way Valve

Item
Uses a DHW flow sensor and PCB to cycle water between the space heating system and the DHW heat
Function
exchanger.
1. No hot water in space heating mode.
Fault
2. No domestic hot water in DHW mode.
DHW supply stops and flow continues in the space heating system when the space heating water
Symptoms
temperature is lower than the set point.
Error codes E016
1. Visual inspection: Check the 3-way valve wiring connections.
Diagnostics
2. Voltage test: Test the voltage meets the specifications shown below.
●
Testing/inspection
●
information

SPACE HEATING: RED + WHITE: ON AC 230 V, OFF 0 V
DHW: RED + PURPLE: ON AC 230 V, OFF 0 V
Confirm voltage as the 3-way valve operating
Description
System Details 53