Navien NP Condensing Tankless Gas Water Heater - Service Manual

4.6.3. Transformer
Navien Part No.
Function
Failure Event
Effects
Error Code
Diagnostic
Color /
Number of wires
BH1419012A Check Point H, K, S
1. To supply power to the main PCB board.
2. Every electrical component of the unit is designed to only work with a
120VAC power supply; therefore, the unit comes equipped with this
transformer.
1. There is no power coming from the transformer.
2. The voltage from the power supply cannot be converted to 120 VAC.
1. The unit does not operate due to lack of power from transformer.
2. A failed transformer can cause electrical damage to other electrical
components within the unit.
N/A
1. Visual inspection: Connection and/or breakage of wires and/
or signs of electrical damage.
2. Voltage check: Check range of voltage shown below.
1. [AC 9 V] Yellow – Yellow : AC 7 ~ 11 V
2. [AC 26 V] White – White : AC 22~33 V
3. [AC 19 V] Blue – Blue : AC 16~24 V
4. [Power trans AC 150 V] Red – Red : AC 123~177 V
5. [Power trans AC 120 V] White – Black : AC 97~138 V
©Navien America Inc. 2010
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NR/NP series service Manual
Version 2.0