Navien Error Codes Explained: A Carlisle, MA Guide

If you smell gas or a CO alarm sounds

Leave the building and call 911 from outside. Don't reset the unit, flip breakers or look for the source, and stay out until officials say it's safe; service comes after that. That instruction overrides everything else on this page.

A Navien tankless water heater that stops heating often leaves a number on its display. Navien error codes record a condition detected by the controls, such as an airflow, water-flow, ignition or electrical fault. A code helps direct diagnosis; it doesn't identify a failed part or prove the appliance is safe. Record it without opening the unit, and don't keep resetting a code that returns.

Write this down first

Before you touch anything, record:

• the tankless water heater code exactly as shown, plus any sub-code or icon
• what was running when it appeared: one shower, several fixtures, a dishwasher, the heat
• the model and serial number from the rating label, without removing a panel
• the date, the weather and any recent work near the heater or its outdoor vents
• whether every hot tap is affected or only one fixture

A reset can clear the display and erase useful context. Record the code and ask for guidance that matches your exact model's owner manual. Don't guess at button combinations or use repeated resets to keep a faulting appliance running. Smoke, flame outside the combustion area, scorching or leaking calls for stopping use; don't approach a damaged unit just to read its label.

What Navien tankless water heater error codes can and can't tell you

Navien tankless water heater error codes point to a system: combustion air and venting, water flow through the heat exchanger, ignition or the electronics. The same root problem can set off more than one code, depending on which sensor trips first.

On a job in Carlisle, MA, one unit showed a venting fault, a flow-related fault and a failed fuse over time. We also found scale inside the heat exchanger. The homeowner reported that hot water had started taking three to four minutes to arrive instead of about 30 seconds. Those were useful findings, but they didn't establish that scale caused every fault or the longer wait. Delivery time also depends on flow, the piping and any recirculation system, so that change deserved its own checks.

Tankless water heater codes differ by brand. If you own a Rinnai, a Noritz or another brand, match the code to your own manufacturer's manual rather than a Navien list. Our Rinnai code guide covers several Rinnai model families. Even within Navien, definitions can vary by series.

Navien error codes list: what we've verified

This table includes only codes whose meaning we've checked in current Navien documentation, tied to the models that documentation covers. For any other code, use the manual for your exact model.

Navien dual venturi problems and code E060

On the NPE-2 models named in the table, the NPE-2 user's information manual lists E060 as abnormal operation of the dual venturi, part of the gas-and-air mixing system on those models, and directs owners to technical support. That's the extent of what the code tells you. It identifies a condition that needs diagnosis, not proof that the venturi needs replacing.

If you see it, record the full code, the model and serial number and what the heater was doing, then contact your installer or a licensed professional. Keep the cover on, and don't attempt adjustments or repeated resets.

When the same code keeps coming back

A returning code means the controls detected the condition again. The fault may be intermittent, so its timing matters: during startup, a long shower, high demand or windy weather. A qualified service professional uses that pattern and the model's diagnostic procedure to test the relevant sensors, water flow, venting or controls. Cabinet access, gas testing and electrical diagnosis aren't homeowner checks.

If inspection finds scale, compare a water test with the installed model's water-quality requirements. Hardness, pH and other parameters answer different questions; a handheld TDS reading cannot replace those tests. Maintenance follows the appliance instructions, actual water conditions and service history. Our water testing service helps establish the water side of that plan.

When diagnosis supports replacement: water heater installation in Carlisle, MA

Sometimes the diagnosis shows a repair isn't worth it: a damaged heat exchanger outside warranty, parts that aren't available, or failures that keep repeating. Then water heater installation in Carlisle, MA is planned from the same evidence: the water test, the venting, the gas supply, the space and your household's hot water demand. You get a written flat-rate price before work starts. Installed, a standard electric tank runs from $2,300, a gas storage heater $2,900 – $6,500 across vent types, a hybrid heat pump up to $7,800 before any rebate, and a condensing tankless $8,500 – $11,000+. Replacing a tankless with another tankless isn't automatic; the choice follows the house.

Getting help

Jeneral Plumbing is owner-operated by a Licensed Master Plumber (MA #9628831-PL-M) with 20+ years in the trade, including seven with a gas utility, factory trained by Navien and Navien Service Specialist (NSS) certified. We're based in Westford, MA, and serve Carlisle and other homes within 20 miles across Middlesex & Worcester County. Our gas appliance work is Massachusetts-only, and we confirm your address, the work and availability when you call. When a unit may qualify for warranty coverage, we help document the claim, and Navien decides it.

During regular hours, a visit carries an $80 dispatch fee — the cost of the visit, waived when you hire us for the work. Off-hours, Sunday and holiday dispatch carries a $599 emergency callout fee, collected prior to dispatch. It's non-refundable and non-negotiable, covers the dispatch only and is never applied to repair work. Call (978) 392-7789 with the code and model number, or see our tankless water heater service.