Navien NPE-240A Service Manual

Version 2.21
28 NPE Service Manual
External Recirculation Mode
To use the external recirculation mode:
1. Connect the water supply to support recirculation. Refer to the
“Installation Manual (page 20)”.
2. Set the 2-way valve inside the water heater to “EXT.“
3. Set the front panel DIP switches at the far left (set of ten) to:
1—OFF; 2—ON.
1 2 3 4 5 6 7 8 9 10
ON ON
The following diagram shows the external recirculation flow for
pre-heating:
External Recirculation Mode
Primary Heat Exchanger
Secondary Heat Exchanger
Buffer
Tank
Flow
Sensor
Domestic
Water
Supply
Hot
Water
Supply
Recirculation
Water Supply
Check
Valve
Water
Adjustment
Valve
2-Way
Valve
Closed
Circulation
Pump

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