Navien NR-20DU Manual Del Usuario página 64

Error Code
E060 Abnormal operation: dual venturi
E109 Abnormal operation: fan motor
E110 Abnormal air pressure
E407 Hot water outlet: thermostat
open or short circuit
E421 Cold water inlet1: thermostat
open or short circuit
E432 Cold water inlet2: thermostat
open or short circuit
E434 Abnormal operation: water
adjustment valve
E438 Abnormal operation: circulation
pump
E439 Abnormal operation: flow sensor
Reason Self-diagnostic / Action
Contact Technical Support at 0844-332-2323
Clean the intake air filter. See the Operation manual.
Ensure that the exhaust pipe is free of obstructions.
Clean the intake air filter. See the Operation manual.
Contact Technical Support at 0844-332-2323
Contact Technical Support at 0844-332-2323
Contact Technical Support at 0844-332-2323
Contact Technical Support at 0844-332-2323
External: Ensure that all water supply and return lines are
open.
Internal: Check the direction of the 2-way valve.
Contact Technical Support at 0844-332-2323