2726
Trouble Possible Cause Remedy
The volume alarm 
does not sound 
even though the 
volume appears to 
be adequate.
Units incorrect 
during input
Measuring flow of 
only hot      water 
instead of hot water 
and cold water 
combined
Refer  to  “Set  a  Desired 
Volume” section to ensure units 
(metric vs. English) and volume 
(displayed  volume  number 
represents 1/10th of the actual 
total flow) is correctly set.
The volume measurement only 
keeps track of the water volume 
that passes through the water 
heater.  If hot water going to a tub 
is combined with cold water, the 
volume computed would not be 
representative  of  the  total 
amount  that  may  have  been 
dispensed.
Unresolved 
problem.
Other assistance 
required.
Consult qualified technician or 
contact  an  authorized  service 
professional. 
ONOFF
UP
DOWN
Combustion
o
F G
o
C L
Water
valve
Code Indication
Remedy
E0 Blower  system  problem 
occurred.
1.  The  blower  jammed  or 
stopped operating because of a 
foreign object.
2. The blower fan suffered a 
mechanical breakdown.  
3. The fan power control module 
has broken down. 
4.  Wiring  harness  or  wiring 
connection somewhere in fan 
connection has come loose. 
1. Check to see if fan turns freely.  
Remove  any  foreign  objects 
jamming the fan.
2. Replace the blower fan.
3.  Replace  the  control  module.
4. Reconnect as required.
E1 Outlet  water  temperature 
sensor error.
1. The sensor plug has come 
loose  or  failed  to  connect 
properly to the circuit board.
2. The sensor broke down (A 
short  circuit,  open  circuit,  or 
accidental  contact  with  the 
casing occurred.)
3.The  circuit  board  of  the 
controller malfunctioned.
4. Sensor is scaled 
1. Plug in the element properly.
2. Replace the temperature sensor.
3. Replace the controller 
4. Clean sensor
E2 Flame detection error.
1. The detection circuitry for 
ignition and flame detection has 
come loose or failed to 
connect.
1.  Connect  the  relevant  circuit 
properly  and  eliminate  the  bad 
connection.
Replace any failed circuit elements.
Whenever  a  failure  occurs,  an  alert  sounds  and  a 
diagnostic code is displayed to indicate the failure mode 
at the time of occurrence.
The following table includes a list of diagnostic codes that 
can be displayed as well as recommended remedies to 
address the problem.
Control Panel Example - Displaying Error Code E2