Navien NHB H Series Installation And Operation Manual page 35

3.6.3 Wiring Diagram - Zone Pump System
The NHB-H boilers can operate a heating system with up to 3 zones. The following is the wiring diagram for a
zone pump system with 3 zones.
Without 24VAC Connections
(250V 3.15A)
CNC1 CNC4 CNC5
ZONE3 ZONE2 ZONE1
Thermostat 3 Thermostat 2
If you have a 24 V thermostat, connect it to the R & C terminals on the boiler's PCB.
Note
●
The C terminals are for optional connections with 24 V thermostat COMMON.
●
CNC6 CNC3 CNV3
DHW LWCO ZONE3
Thermostat 1
Pump Ground
CNB1
CON1 CON2
L
ZONE3 Pump FUSE
(250VAC_10A)
ZONE2 Pump FUSE
(250VAC_10A)
CNV2 CNV1
ZONE2 ZONE1
CNG1
CNP1
ZONE1 Pump FUSE
(250VAC_10A)
CNC2
Boiler Pump FUSE
(250VAC_10A)
CNP2
N
Live
Neutral
OUT
Zone Pump 3
IN (max. 2.5 A)
OUT
Live
IN
Neutral
OUT
Zone Pump 2
(max. 2.5 A)
IN
CNF1
Live
Neutral
Zone Pump 1
(max. 2.5 A)
OUT
Live
IN
Neutral
Boiler Pump
(max. 2.5 A)
OUT
Installing the System Piping 35