What does error code E031 mean on a Navien tankless water heater?

Burner overheating. The burner is overheating.

Can I fix Navien code E031 myself?

Start with these safe checks: Turn the heater off. Navien says contact technical support.

When should I call a technician for code E031?

Navien says contact 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 E031: Burner overheating

Navien NPE-2 tankless water heaters

What E031 means

The burner is overheating.

Likely causes

Burner or combustion problem

Safe first checks

Turn the heater off.

When to stop

Navien says contact 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.