Problem Center · Navien
Navien Boiler Error Code — What Does It Mean?
Your Navien combi boiler, boiler or tankless water heater is showing an error.
What could cause this?
- Ignition or flame detection faults
- Venting or air intake problems
- Water flow or pressure problems
- Temperature sensor faults
- Condensate blockage
- Gas supply issues
What you can safely check
- Photograph the error code and the unit’s label
- Note the pressure reading if it’s a boiler
- Note whether heat, hot water or both are affected
Don't open electrical panels or equipment cabinets, handle refrigerant, work on gas or combustion components, or bypass safety controls.
When it requires a professional
If you smell gas, leave the building and call your gas utility or 911 from outside. Error codes describe a symptom, not always the cause. Request service with the photo.
How Air Mechanical diagnoses it
As a Navien Pro, we read the code in the context of the full installation — venting, gas, water and controls.
Every diagnosis starts with the system as it actually exists — equipment, controls, wiring and installation. The equipment has a brand. The problem has a solution.