Navien NPE-240A Installation Manual

Installing the Water Heater 23
3.4.3 External Pump Wire Connection
An external pump may be connected to the water heater for
recirculation applications. When selecting a circulator, it shall be
sized to maintain a flow of 2-4 GPM through the water heater.
Follow the instructions below when connecting the pump wire
accessory to the PCB.
WARNING
Failure to follow the instructions below may result in property
damage, personal injury or death. To avoid the danger of
electric shock, make sure that the water heater is turned off
before connecting the wire to the PCB.
<Specications>

Maximum Power Consumption: 150 W, 1.5 A

Length: 6 ft (183 cm)
Ú
When using a pump with larger power requirements than the listed
specication above, a relay should be used to ensure proper operation.
1. Remove the water heater front cover by loosening the
4Phillips head screws securing it to the case.
2. Locate the power switch on the right side of the front panel
and switch the system off.
Turn the switch off.
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