Brand guide
Navien error codes
Match the equipment family and displayed code before following any check.
Official Navien material describes E003 as Ignition failure. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E004 as False flame detection. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E012 as Flame loss. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E016 as Overheating of the heat exchanger. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E030 as Exhaust overheating - the water heater shuts down when the flue temperature exceeds 149 degrees F (65 degrees C). This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E046 as Abnormal operation: limit control. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E047 as Abnormal operation: exhaust thermostat. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E060 as Abnormal operation: dual venturi. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E109 as Abnormal operation: fan motor. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E110 as Abnormal air pressure. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E407 as Hot water outlet: thermistor open or short circuit. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E421 as Cold water inlet 1: thermistor open or short circuit. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E432 as Cold water inlet 2: thermistor open or short circuit. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E434 as Abnormal operation: water adjustment valve. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E438 as Abnormal operation: circulation pump. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E439 as Abnormal operation: flow sensor. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E441 as Hot water inlet 2: thermistor open or short circuit. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E445 as Abnormal operation: bypass mixing valve. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E515 as Abnormal operation: PCB (printed circuit board). This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E517 as Abnormal operation: DIP switch setting. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E593 as Abnormal operation: front panel key. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E615 as Abnormal operation: input and memory. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E736 as Abnormal operation: cascade communication. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E740 as Abnormal operation: outdoor temperature sensor. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E760 as Flushing/service alarm. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E782 as Abnormal operation: main panel communication. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.
Official Navien material describes E785 as Abnormal operation: flow switch/sensor. This guide records the cited product-family scope, safety-reviewed owner checks, and service limits.