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Appendixes
6.8 Navien HotButton Kit (Optional)
The Navien HotButton kit is an add-on input board for the water heater. It adds
signal input functions to the water heater for more efficient DHW hot water
recirculation functionality.
With the HotButton kit, DHW recirculation is carried out exactly when the actual
demands arise. This prevents energy loss caused by unnecessary operation of
the burner and pump throughout the day.
The HotButton kit can receive signals from multiple push buttons installed in
various areas and performs optimal DHW recirculation only when there is a
demand for hot water.
6.8.1 Basic Principles
The following diagram shows the basic operation of the water heater system with the Navien HotButton kit.
CAUTION
The Navien HotButton can be used ONLY with a water heater system configured for DHW recirculation.
* When the optional temperature sensor is installed, it must be insulated.
The sensor wire may be extended by up to 100 ft (30 m) using 22AWG wire.
DHW return
(to recirculation inlet)
(to hot water fixtures)
DHW supply
Cold water line
City water supply
To cold water inlet
Push button
contact signal
Temperature
sensor (optional)
Push button
contact signal
Push button
contact signal
1 2 3
4
ON
SW1
CE1
CE2
U1
C1
C2
C7
R6
PC1
12 V
5 V
SIGNAL
SIGNAL
1
GND
R5
R9
R8
C3
R1 R2
R7 D1
CON3
CON5
CON2
CON1
SIGNAL
2
SENSOR I
RA1
