Navien NCB-190/060H, Installation & Operation Manual

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43 Installing the System Piping
3.7.4 Wiring Diagram - Zone Pump System with DHW Recirculation
NCB-H boilers can use both the 3 zone heating system and the DHW recirculation feature. The following wiring
diagram shows the 3 zone system and the DHW external recirculation feature.
Without 24VAC Connections
N
A/H
D H
W
PRI
L
N
L
N
L
N
L
N
L
Z3
Z2
Z1
SUPPLY
TEMPERATURE SENSOR
RETURN OUTDOOR T/S_ZONE3
R W C
T/S_ZONE2
R W C
T/S_ZONE1
R W C
AC24VN
AC24VL
lLWCO
R
W
C
T/S
_R
ecir
COM
NO
NC
ZONE
_V
/V3
COM
NO
NC
ZONE
_V
/V2
COM
NO
NC
ZONE
_V
/V1
SUPPLY
TEMPERATURE SENSOR
RETURN OUTDOOR T/S_ZONE3
R
W
C
T/S_ZONE2
R
W
C
T/S_ZONE1
R
W
C
AC24VN
AC24VL
lLWCO
R
W
C
T/S_Recir
COM
NO
NC
ZONE_V/V3
COM
NO
NC
ZONE_V/V2
COM
NO
NC
ZONE_V/V1
Thermostat 3
Thermostat 2
Thermostat 1
N
A/H
DHW
PRI
L
N
L
N
L
N
L
N
L
Z3
Z2
Z1
Zone pump 1
(max. 2.5 A)
Zone pump 2
(max. 2.5 A)
Zone pump 3
(max. 2.5 A)
Recirculation pump
(max. 2.5 A)
Recirculation Timer,
Aquastat,
or HotButton
Push Button
Pump Ground
* If the DHW recirculation menu is set to the Always On, Intelligent, or Weekly option, no aquastat or additional HotButton Push
Button is required.
Note
●
The C terminals are for optional connections with 24 V thermostat COMMON.
●
When using combi pre-heat, using a recirculation pump is not necessary. Select combi pre-heat in
the DHW recirculation menu.
●
When using external recirculation, install a recirculation pump and select external recirculation in
the DHW recirculation menu.