Navien NPE-240A Service Manual

System Details 59
4.11.2 High Limit Switch
Check Point Check Point
Function
1. Overheat prevention switch.
2. If the unit detects extremely high temperatures, it will automatically trip and shut down the unit.
3. Excessively high water temperatures (more than 197.6°F or 92°C) in heat exchanger will activate the high
limit switch.
Failure Event Unable to detect excessively high water temperature if switch fails.
Effects Unable to shut down the water heater if the water temperature from the heat exchanger exceeds 197.6°F (92°C).
Error Code E016, E046
Diagnostic
1. Visual inspection: Connection and/or breakage of wires.
2. Resistance check: Check range of resistance shown below.
Color/Number
of wires
Resistance range : under 1.0 

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