Navien E012 (flame loss): what to check

Navien display

E012

“Flame loss”

NPE-A2, NPE-S2, NPN · NPE-2 User's Information Manual, p. 17; NPN User's Information Manual, p. 22
Owner checks, then technician

What it means

E012 means the burner was lit and the heater then lost the flame. Navien’s remedies cover the air intake filter and the grounding of the power cord, and on NPN models also the gas type setting NPE-2 User’s Information Manual, p. 17; NPN User’s Information Manual, p. 22. Only the filter comes with an owner procedure, and only in the NPE-2 manual p. 14.

Check these first

1. Reset the heater once. On NPE-A2 and NPE-S2 models, press Back NPE-2 User’s Information Manual, p. 10. On NPN models, press Reset on the front panel, or OK on the remote for outdoor models NPN User’s Information Manual, pp. 12, 21.
2. If E012 returns on an NPE-A2 or NPE-S2, clean the air intake filter NPE-2 User’s Information Manual, p. 14. Turn the heater off with the Power button and disconnect its power supply before you remove the front cover; the manual warns of electric shock otherwise p. 6.
3. The filter sits at the top left of the heater, held in place by one screw. Take it out of its plastic holder, scrub it with a toothbrush under clean running water, and let it dry completely before it goes back in p. 14.
4. Refit the filter and the front cover, reconnect power, and turn the heater on with the Power button p. 14. Never run the heater with the front cover open NPE-2 User’s Information Manual, p. 5.
5. If E012 comes back with a clean filter, call for service: an authorized technician, a licensed professional or Navien Technical Support at 1-800-519-8794 NPE-2 User’s Information Manual, p. 16; NPN User’s Information Manual, p. 21.

Navien recommends cleaning this filter every 3–4 months as routine maintenance NPE-2 User’s Information Manual, p. 14.

When to call a licensed technician

• E012 keeps returning after a reset and a filter cleaning.
• Both tables also say to make sure the electrical cord is properly grounded NPE-2 User’s Information Manual, p. 17; NPN User’s Information Manual, p. 22. Navien leaves the power connection to licensed professionals NPE-2 Installation & Operation Manual, p. 59; NPN Installation and Operation Manual, p. 46, so have an electrician or technician check the grounding.
• On NPN models, the gas manifold and the fuel DIP switch setting must match the gas supplied NPN User’s Information Manual, p. 22. Changing between natural gas and propane takes a Navien conversion kit installed by a qualified service agency NPN Installation and Operation Manual, p. 19.
• Anything behind the front cover other than the NPE-2 air intake filter NPE-2 User’s Information Manual, p. 6.

Notes for different models

On NPN models the table also says to clean the intake air filter and refers to page 19. Page 19 of the NPN User’s Information Manual covers the cold water inlet filter, and the NPN manuals describe no air intake filter: the parts lists in the NPN Installation and Operation Manual pp. 9–10 name only a water inlet filter. Before you open an NPN heater for this step, ask Navien Technical Support (1-800-519-8794) which filter the table means.

The NR-21DU remote manual lists the filter and grounding checks for E012 without the NPN gas type check, and refers to “the Operation manual” without a page number NR-21DU Remote Controller Manual, p. 30.

Related Navien codes

• E003 “Ignition failure”
• E004 “False flame detection”
• E110 “Abnormal air pressure”

All Navien codes

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