Can I fix Navien code E030 myself?

Start with these safe checks: Clean the cold water inlet filter. Flush the heat exchanger. If it continues, contact Navien technical support.

When should I call a technician for code E030?

If it continues, contact Navien technical support. Smell gas? Leave right away, don't touch light switches or phones inside, and call your gas utility or 911 from outside. Never open a gas valve, burner, gas line, vent or flue connection, or bypass a safety switch. Repeated lockouts, scorching, soot, or a CO alarm mean shut it off and call a licensed gas technician.

Navien tankless water heater error code

Navien tankless water heater code E030: Exhaust overheating

Navien NPE-2 tankless water heaters

What E030 means

The heater shut down because the flue temperature went above 149°F (65°C).

Likely causes

Clogged cold water inlet filter
Scale in the heat exchanger

Safe first checks

Clean the cold water inlet filter.
Flush the heat exchanger.

When to stop

If it continues, contact Navien technical support.

Checked against: Navien NPE-2 user's information manual: understanding error codes. Codes can differ by model and year, so confirm with your owner's manual.