Navien Boiler Error Codes
Complete guide to Navien boiler and tankless water heater error codes with safety information and troubleshooting steps.
Important Safety Notice
Navien boilers have built-in safety features. When the system detects a problem, it will lockout to protect you and your property.
Do not repeatedly reset the unit. If an error persists, call a licensed technician.
Call Now: 778-909-5731Safety Level Key
SafeSystem protected, low risk
CautionMonitor and call technician
DangerCall technician immediately
Common Navien Error Codes
Error Code E003
Ignition Failure
What You Can Check
- •Verify gas is on
- •Check circuit breaker
- •Look for error pattern
Error Code E004
False Flame Detection
What You Can Check
- •Turn off unit
- •Wait 5 minutes
Error Code E005
Exhaust Overheat
What You Can Check
- •Turn off unit immediately
- •Check for blocked vents
Error Code E006
Exhaust Thermistor Failure
What You Can Check
- •Note when error occurs
Error Code E007
Outlet Thermistor Failure
What You Can Check
- •Note temperature display
Error Code E008
Inlet Thermistor Failure
What You Can Check
- •Check water supply
Error Code E010
Air Pressure Switch Error
What You Can Check
- •Check exhaust vent for blockages
- •Look for wind interference
Error Code E012
Flame Loss
What You Can Check
- •Check gas valve is open
- •Verify no gas outages in area
Error Code E016
Overheat - Flow Issue
What You Can Check
- •Turn off unit
- •Check for closed valves
Error Code E027
Water Flow Sensor Error
What You Can Check
- •Check water supply
- •Verify isolation valves are open
Don't See Your Error Code?
Navien has many error codes. If your code isn't listed here, or if you need help diagnosing the issue, our technicians have the expertise and tools to resolve any Navien error.
Call 778-909-5731