Navien NPE-240A Service Manual

Version 2.21
68 NPE Service Manual
4.11.11 Flow Sensor
Part Check Point
Function To detect water flow in GPM (Gallons Per Minute) for steady hot water temperatures.
Failure Event
1. Unable to detect or measure water flow rate.
2. Damage to and/or water leakage from the water flow sensor.
Effects Ignition sequence does not start.
Error Code E439
Diagnostic
1. Visual inspection: Connection and/or breakage of wires.
2. Visual Inspection: Check for damage and/or scale formation on sensor.

Navien NPE-240A Specifications

General

Type	Tankless
Fuel Type	Natural Gas or Propane
Energy Factor	0.97
Energy Efficiency	97%
Voltage	120V
Ignition Type	Electronic
Maximum Input	199, 900 BTU/h
Water Connection Size	3/4"
Gas Connection Size	3/4"
Warranty	15-year on heat exchangers, 5-year on parts, 1-year on labor
Dimensions	17.3" W x 13.2" D x 27.4" H