What does error code E012 mean on a Navien tankless water heater?

Flame loss. The flame went out during operation.

Can I fix Navien code E012 myself?

Start with these safe checks: Clean the intake air filter as shown in the manual. Make sure the power cord is properly grounded. If it continues, contact Navien technical support.

When should I call a technician for code E012?

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 E012: Flame loss

Navien NPE-2 tankless water heaters

What E012 means

The flame went out during operation.

Likely causes

Dirty intake air filter
Poor grounding
Gas supply problem

Safe first checks

Clean the intake air filter as shown in the manual.
Make sure the power cord is properly grounded.

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.