John Wood Takagi - 240H-340H-540H - Manual (Page 45)

45
Page
-Fault Analysis of Error Codes-
If the error code is displayed on the computer board of the water heater or remote controller and/or
temperature controller, please check the following. After checking, consult with the manufacturer.
Troubleshooting
Owner's Guide
Remote
Green
LED
Malfunction
description
Diagnosis
031 One Time Incorrect DIPswitch
setting
• Check the DIPswitch settings on the PCB. (Part #701).
101 Five Times Warning for the
“991” error code
• Check the gas type of the water heater.
• Check if there is any blockage in the intake air and/
or exhaust.
• If the water heater is installed as a direct-vent system,
check whether there is enough distance between the
intake air terminal and the exhaust terminal.
• Check the altitude/elevation of area of where the
water heater is installed.
• Check if there is grease and/or dirt in the burner (Part
#101) and the fan motor (Part #103), especially if the
water heater has been installed in a contaminated area.
111 Three Times Ignition failure • Check if the Hi-limit switch (Part #412) is properly
functioning.
• Check for connection/breakage of wires (Part #413, 708,
709, 710, 712), burn marks on the computer board (Part
#701), and/or soot on the flame rod (Part #108).
• Check if there is a buzzing spark ignition sound
coming from the burner (Part #101) when water
heater prepares for combustion.
• Listen for the double “clunk” sound coming from gas
valve assembly (Part #102) when water heater goes
into combustion.
• Check if there is leaking from heat exchanger. (Part #401)
121 Three Times Loss of flame • Check if the Hi-limit switch (Part #412) is properly
functioning.
• Check for connection/breakage of wires (Part #413,
708, 709, 710, 712), burn marks on the computer
board (Part #701), and/or soot on the flame rod
(Part #108).
• Check if there is leaking from heat exchanger. (Part #401)
311 Two Times Outlet thermistor
failure (T-H3J-DV /
240H and T-H3S-DV
/ 340H only)
Heat exchanger
thermistor failure
(T-H3-DV / 540H
only)
• Check for connection/breakage of wires and/or
debris on thermistor. (Part #407, 408, 411, 715)
321 Two Times Inlet thermistor
failure
331 Two Times Outlet thermistor
failure (T-H3-DV /
540H only)
341 Two Times Exhaust thermistor
failure