Navien NPE-240A2 Installation Manual

121Appendixes
8.5 Ladder Diagram
LIVE
NEUTRAL
120VAC
Relay 2
Relay 3
Igniter
Circulation Pump
Speed Control
Transformer
Primary
Sencondary
MCU 1 MCU 2
Flame rod
WD-RSS
DC24V
Relay 1
Relay 3
Driving Circuit
Flow Sensor
APS
DC12V
Fa n
Hall Sensor
BLDC-FAN
Water Ad justment
Valve
Flow Control
DC15V
Vent
Installation
Detector
Inlet
Thermistor 2
Outlet
Thermistor 1
Outlet
Thermistor 2
UART
Comm unication
Interface
FRONT
PANEL
Communication
Interface
FUSE(5A)
HOT-BUTTON
Inlet
Thermistor 1
EMI
FILTER
PWM
Mixing Valve
(NPE-S2 Serise Only
DC 5V
Flow Control
Venturi
Relay 4
AC130
Trans
V
Relay 2
Relay 4
Exhaust
Thermistor
HTL switch
Buner
TDS Sensor
Ready Link Interface
Relay 1
External Pump
DC 9V
HTL switch
Heat Exchanger
GAS V/V1
GAS V/V2
Option
NPE-A2 Serise Only
[NPE-150S2, 180A2/S2, 210A2/S2, 240A2/S2]

Navien NPE-240A2 Specifications

General

Type	Tankless
Fuel Type	Natural Gas or Propane
Energy Factor	0.96
Water Connection Size	3/4" NPT
Gas Connection Size	3/4" NPT
Voltage	120 V
Ignition Type	Electronic
Flow Rate	11.2 GPM
Vent Size	2"/3"
Installation Type	Wall Mounted
Venting	Direct Vent
Warranty	15-Year Heat Exchanger, 5-Year Parts, 1-Year Labor
Max Input	199, 900 BTU/h