John Wood Takagi - 320H-520H - Manual (Page 32)

32
Error Codes
The 520H units are self diagnostic for safety and conve-
nience when trouble shooting.
If there is a problem with the installation or the unit, it will
display a numerical error code on the 3- digit 7-Seg. LED
on the computer board (visible through a window on the
front cover) or remote controller (if installed) to commu-
nicate the source of the problem.
Consult the table on the following page for the cause of
each error code.
3 digit 7-
Seg. LED
Error code on the computer board
Error code on the
remote controller
Single Unit Installations
The 7-Seg LED and remote controller displays the whole
3-digit error code.
Example: If your unit has the “321" error code (inlet thermis-
tor failure)
Water heater: It will display “321" on the 7-Seg LED.
Remote controller: It will display “321" on its screen.
Easy-Link System
The 7-Seg LED of the individual unit with the error in ques-
tion displays the whole 3-digit error code. The remote con-
troller (if installed) displays a 3-digit number which signifies
which unit has the error, and what the error code is.
Example: If Unit #2 has the “321" error code (inlet thermis-
tor failure)
Water heater #2: It will display “321" on the 7-Seg LED,
just like in the Single Unit example.
Remote controller: It will display “232" on its screen. The
first “2" indicates that Unit #2 has the error. The “32" indi-
cates the first two digits of the “321" error code.
•
•
•
•
•
•
•
Fault Analysis Of Error Codes
If there is a problem with the installation of the 520H, it will
display a numerical error code on the 7-seg LED of the
computer board or the remote controller (if installed) to com-
municate the source of the problem.
Error
Code
Malfunction description Diagnosis
031 Incorrect DIPswitch settings
Check the
DIPswitch set-
tings on PCB
101
Warning for the “991" error
code
Call the
manufacturer’s
Technical Dept. at
1-888-479-8324
111 Ignition failure Check gas
supply
121 Loss of flame
311 Output thermistor failure
Call the
manufacturer’s
Technical Dept. at
1-888-479-8324
321 Inlet thermistor failure
331 Mixing thermistor failure
341
Exhaust thermistor failure
(520H only)
391 Air-fuel Ratio Rod Failure
441
Flow Sensor Failure (Only
Easy-Link system)
510 Abnormal Main Gas Valve
551
Abnormal Gas Solenoid
Valve
611 Fan Motor Fault
621
Exhaust fan motor Fault
(520H only)
631 Abnormal External Pump
651
Water Control Valve Fault
(Flow Adjustment function)
(Only Easy-Link system)
661
Water Control Valve Fault
(Bypass valve function)
701 Computer board Fault
711
Gas Solenoid Valve drive
circuit failure
721 False Flame Detection
741
Miscommunication between
water heater and remote
controller
761
Miscommunication in
Easy-Link
941
Abnormal exhaust tempera-
ture (520H only) Lower the set
temperature
991 Imperfect combustion
Call the
manufacturer’s
Technical Dept. at
1-888-479-8324