Water Pressure Sensor - Navien NHB-055 Service Manual

4.9.12 Water Pressure Sensor

Part
Function
Failure Event
Effects
Error Code
Diagnostic
Testing/inspection
information
76 NHB Service Manual
Detects water pressure in the heating system.
Unable to detect or measure to change in water pressure.
Water filling system does not operate automatically
E302, E352, E353
1. Visual inspection: check the circulation pump connection wire.
2. Voltage check: Check range of voltage shown below.
Black-Red : DC 0~5V
Check Point
Legend to cross-section drawing
1. Pressure connection
2. Ceramic sensor
3. Amplifier electronics
4. Cover
5. Electrical connection (RAST 2.5)
Version 1.0