Navien NPE-240A Service Manual

System Details 69
4.11.12 Primary Heat Exchanger
Part Check Point
Function
1. Main part for heat transfer from the burner.
2. There are multiple paths of water pipes on the heat exchanger surface as well as inside the combustion
chamber which minimizes the heat loss.
Failure Event
1. Water and/or exhaust gas leakage through a crack.
2. Improper heat transfer can cause the water in the heat exchanger to boil due to possible scale formation.
Effects
1. Exhaust gas leakage.
2. Excessive heating of the water that produces boiling noises.
Error Code E016, E030, E047
Diagnostic
1. Visual inspection: Check if there is a crack on the surface of heat exchanger.
2. Sound inspection: Check if boiling occurs inside the unit.
Color/Number
of wires
N/A

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