Navien Water Heater Error Code 432: How to Fix It

Q: What does error code 432 mean on a Navien water heater?

Error 432 indicates a thermistor compensation fault, meaning the temperature sensors are not working properly.

Q: Can I reset Navien error 432 without a technician?

Yes, a power cycle (turning off power for 60 seconds) may clear the fault temporarily. However, if the problem persists, further diagnosis is needed.

Q: How much does it cost to fix Navien error 432?

If you DIY replace a thermistor, the part cost is around $20-50. A professional service call can range from $150-$300.

Q: Is error 432 serious?

It is a medium-severity error. The heater will likely not operate until fixed, but it does not indicate immediate danger.

Q: Where are the thermistors located on my Navien water heater?

They are typically on the cold water inlet and hot water outlet pipes near the top of the unit.

Abstract

Error code 432 on your Navien tankless water heater indicates a thermistor compensation fault. This means the water temperature sensors are not reading correctly, which can cause the unit to shut down as a safety precaution. Below are steps to diagnose and resolve the issue.