Navien Error Code E030: Exhaust Overheat Sensor

Severity
Warning
Type
digital display
Where to look
front panel
Estimated repair cost: $100 — $350 (parts + labor)
Warning: Your Navien boiler has detected an overheating exhaust issue and has shut down to prevent damage.

How to Fix Navien Code E030

  1. Check the exhaust vent for any signs of blockage or restriction. Ensure it is clear and properly connected to the boiler.
  2. Inspect the exhaust overheat sensor for any visible damage or discoloration. If you suspect it is faulty, it's best to call a professional for replacement.
  3. If the issue persists, call a licensed HVAC technician to diagnose and repair the problem.

How to Reset Navien Code E030

  1. Turn off the unit using the power button on the front panel.
  2. Turn off the gas supply valve.
  3. Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
  4. Restore power at the breaker, then open the gas valve.
  5. Turn the unit back on. If the error returns, the underlying issue needs repair.

Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.

What Does Navien Error Code E030 Mean?

The E030 error on your Navien boiler indicates that the exhaust overheat sensor has detected temperatures exceeding the safe limit. This sensor is designed to protect your boiler from overheating, which can cause damage to the unit and potentially lead to a safety hazard. When this error occurs, your boiler will shut down to prevent any further issues.

Common Causes

  • Blocked or restricted exhaust venting, preventing proper heat dissipation
  • Faulty exhaust overheat sensor
  • Incorrect venting material or size
  • Overheating due to a separate issue, such as a failed heat exchanger

Diagnostic Steps

If... Check Expected
Boiler is not running Exhaust vent temperature Below 200°F (93°C) when boiler is off
Boiler is running Exhaust vent temperature Below 350°F (177°C) for condensing boilers, below 450°F (232°C) for non-condensing boilers

Applicable Navien Models

Source Documentation

Referenced in 6 official Navien technical manuals.

ManualPageReasonAction
NFB-H Installation & Operation Manual116Exhaust OverheatCheck flow, clean system filters.
Navien NCB-H Installation & Operation Manual129Exhaust OverheatContact technical support at 1-800-519-8794.
Navien NFB-H Installation & Operation Manual116Exhaust OverheatCheck flow, clean system filters.
Navien NFC-H Installation & Operation Manual127Abnormal exhaust temperatureManual RESET Alarm
Navien NHB-H Installation & Operation Manual119Exhaust OverheatCheck flow, clean system filters.
Navien NPF Installation & Operation Manual125Abnormal exhaust gas temperature (Lock Out)This error occurs when the overheat controller on the exhaust is initiated due to an abnormal exhaust gas temperature. ● Stop operating the furnace and contact Technical Support at 1-800-519-8794.

Replacement Parts

Part OEM Number Est. Cost Where to Buy
Exhaust Overheat Sensor 800-1000-0000
Exhaust Vent

Related Codes on Same Models

Other codes that affect the same Navien model families as E030.

Code Description Severity
E001 Ignition Failure Warning
E003 Abnormal Ignition Warning
E004 False Flame Detection Warning
E012 Flame Loss Warning
E016 Overheating Warning
E031 Inlet Thermistor Open/Short Warning
E046 Outlet Thermistor Open/Short Warning
E047 DHW Thermistor Open/Short Warning
E060 Fan Motor Abnormality Warning
E109 Fan Motor Speed Low Warning