40
DIAGNOSTICS
Self Monitoring
This unit has the ability to check its own operation continuously. If an error occurs, a message will flash on the
digital monitor of the front panel.
This assists with diagnosing the error, and may enable you to overcome a problem without a service call. Please
quote the code displayed when inquiring about service.
Code display
Cause
Remedy
E1
□
Remaining flame detected
□
Call service center
□
Ignition failure
□
Check gas line, ignitor, flame rod
- doesn't detect flame signal
□
Check wire connection of 8p wire and ignitor wire
□
Check ignition noise
□
Check gas type and manifold pressure
□
Abnormal combustion
□
Check the gas supply in enough
-after detection of flame signal,
□
Check the gas valve
system lose the signal
□
Check wire connection of 8p wire and ignitor wire
□
Check gas type and pressure are correct
□
Check power supply for proper voltage
□
□
Check the outlet thermistor
□
Check wire connection of 14p wire and thermistor wire
□
□
Check the outlet thermistor
□
Check wire connection of 14p wire and thermistor wire
□
□
Check the H/E thermistor
□
Check wire connection of 14p wire and thermistor wire
□
□
Check the H/E thermistor
□
Check wire connection of 14p wire and thermistor wire
□
□
Check the inlet thermistor
□
Check wire connection of 14p wire and thermistor wire
□
□
Check the inlet thermistor
□
Check wire connection of 14p wire and thermistor wire
□
□
Check DC motor
□
Check wire connection of 6p wire
□
□
Check the water filled in tank
□
Check water pressure switch
□
Check connection of 14p wire and water pressure wire
□
□
Check the adjust control valve movement noise
□
Check wire connection of 16p wire and adjust valve wire
□
□
Check the mixing control valve movement noise
□
Check wire connection of 16p wire and mixing valve wire
□
□
Check the adjust control valve movement noise
□
Check wire connection of 16p wire and adjust valve wire
□
□
Check the mixing control valve movement noise
□
Check wire connection of 16p wire and mixing valve wire
□
□
Check the thermostat
□
Check the thermal fuse
□
Check the air pressure switch
□
E2
E3
E4
E5
An outlet thermistor open
An outlet thermistor short
Power line of main gas
valve is open
An inlet thermistor short
A DC motor failure
Adjust control valve
initialization failure
Mixing control valve
initialization failure
E8
An inlet thermistor open
Adjust control valve is not
connected
No filled water in tank or
pressure switch failure
E9
E11
E13
E6
A H/E thermistor open
E7
A H/E thermistor short
E24
Mixing control valve is not
connected
E23
E26
□
Call service center
E27
Rotation of a DC fan is
too high
E28
E30
□
Check wire connection of gas valve, thermostat,
thermal fuse and air pressure switch
● Error Code Diagnosis
