Takagi Error Codes

    Takagi Error Codes for Tankless Water heaters

    Check your Takagi error codes below as there could be a risk of fire, explosion, carbon monoxide poisoning, or even a potential scalding hazard. Service and repairs on these heaters must be by a qualified service professional.

    Watch out: some errors are signaling a dangerous condition!

    All units are put into a self diagnostic state for all Takagi error codes, this is for your safety and convenience when trouble shooting.

    Error Code Display Location

    Takagi error codes may be displayed in different locations on some units. The 3‐digit 7‐Seg LED displays error code, or the TM‐RE30 (if installed) displays the 3‐digit error codes. Alternatively for Easy-Link System units, The 7‐Seg LED of the individual unit with the error in question displays the whole 3‐digit error code.  

    The TM‐RE30 (if installed) displays a 3‐digit number which signifies which unit has the error, and what the error code is if you have a multi unit system.  

    If there is a problem with the installation or the unit, it will display a numerical error code on the Remote Controller (if installed), or on the 7‐Seg LED on the computer board (510 (T‐D2). If your systems doesn’t have an LCD or remote controller Takagi has installed a red LED that will flash the corresponding error codes. (110 (T‐KJr2), 310 (T‐K4)) use this method to display the source of the problem.  

    Tips For Reading the Codes

    Consult the chart for the cause of each error code.

    If your water heater model is not listed in the chart below then the error code in this table may not apply to your system.

    See your water heater manual or troubleshooting manual for your specific water heater model for expanded detail about the meaning and the corrective steps for each of these error codes. If all else fails try rebooting the system by unplugging it and waiting 2 minutes before plugging it back it.

    Takagi Error Codes
    Error CodeIssueModelsReplacement Parts
    1Wrong dip switch setting Red LED / Computer Board Fault110 (T‐ KJr2), 310 (T‐K4) Remote1. Computer Circuit Board
    2. Computer Circuit Board
    3. Computer Circuit Board
    2Inlet Thermistor / Output Thermistor / Air-fuel ratio rod failure110 (T‐ KJr2), 310 (T‐K4) Remote1.Outlet Thermistor
    2.Thermistor
    3Ignition Failure / Flame Loss110 (T‐ KJr2), 310 (T‐K4) Remote1. Flame Sensor
    2. Flame Rod
    4Abnormal Fan Motor110 (T‐ KJr2), 310 (T‐K4) Remote1. Fan Motor
    5Warning for 991 error code / Abnormal Combustion110 (T‐ KJr2), 310 (T‐K4) RemoteNot Applicable
    6Abnormal Gas Valves / Abnormal Solenoid Gas Valve / False Flame Detection110 (T‐ KJr2), 310 (T‐K4) Remote1. Gas Valve Assembly
    2.Manifold and Gas Valve
    03Wrong dip switch setting, 110 (T‐ KJr2), 310 (T‐K4) Remote110 (T‐ KJr2), 310 (T‐K4) RemoteNot Applicable
    10Warning for 991 Error Code110 (T‐ KJr2), 310 (T‐K4) RemoteNot Applicable
    11Ignition failure110 (T‐ KJr2), 310 (T‐K4) Remote1. Flame Sensor
    2. Flame Rod
    12Flame loss110 (T‐ KJr2), 310 (T‐K4) Remote1. Flame Sensor
    2. Flame Rod
    31Output Thermistor110 (T‐ KJr2), 310 (T‐K4) Remote1. Output Thermistor
    2. Output Thermistor
    32Inlet Thermistor110 (T‐ KJr2), 310 (T‐K4) Remote1. Thermistor
    39Air-Fuel Ratio Rod Failure110 (T‐ KJr2), 310 (T‐K4) RemoteNot Applicable
    51Abnormal Gas Valves110 (T‐ KJr2), 310 (T‐K4) Remote1. Gas Valve Assembly
    2.Manifold and Gas Valve
    3. Manifold and Valve
    55Abnormal Solenoid Gas Valve110 (T‐ KJr2), 310 (T‐K4) Remote1. Gas Valve Assembly
    2.Manifold and Gas Valve
    3. Manifold and Valve
    61Abnormal Fan Motor110 (T‐ KJr2), 310 (T‐K4) Remote1. Fan Motor
    2. Fan Motor
    3. Fan without pressure port
    4. Fan with pressure port
    5. Fan Motor
    70Computer board fault110 (T‐ KJr2), 310 (T‐K4) Remote1. Computer Circuit Board
    2. Computer Circuit Board
    3. Computer Circuit Board
    72False flame detection110 (T‐ KJr2), 310 (T‐K4) Remote1. Flame Sensor
    74Remote controller communication failure110 (T‐ KJr2), 310 (T‐K4) Remote1. Remote
    2. Remote
    99Abnormal combustionT-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Overheat Cutoff Fuse
    031Wrong dip switch setting, possibly LP gas set when the fuel is Natural gas, or vice versaT-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Not Applicable
    070Computer board failure – see 701T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Computer Circuit Board
    2. Computer Circuit Board
    3. Computer Circuit Board
    072False flame detected – see 721T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Flame Sensor
    074Remote control problem – see 741, 751T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Remote
    2. Remote
    099Improper combustion – see 991
    Watch out: this is an unsafe condition with a CO hazard.    		T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Not Applicable
    101Improper combustion.

     

    Watch out: this is an unsafe condition. Look for a blocked flue or chimney (or downdrafts in the chimney) or a problem with the draft inducer fan.

    Warning for 991 error code

    		T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Not Applicable
    111Ignition failure; the burners do not light. Check for a bad igniter, flame sensor, gas valve. Check for gas supply. Check for a blown fuse on the circuit board.T-D2, T-H2-OS, T-M32, T-M501.Ignighter
    2.Ignighter
    3.Ignighter
    4.Flame Sensor
    5.Gas Valve Assembly
    112Burner flame lost. See code 111 above.T-D2, T-H2-OS, T-H3-DV/OS, T-M32, T-M50See Parts For Code 111
    121Burner flame lost. See code 111 above.T-D2, T-H2-OS, T-H3-DV/OS, T-M32, T-M50See Parts For Code 111
    311Output thermistor failure. Check the thermistor and its wires on the heat exchanger. Replace the thermistor if you don’t see a loose or disconnected wire.T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Output Thermistor
    2. Output Thermistor
    321Input / Inlet thermistor failure. Check the thermistor and its wires at the water inlet. Replace the thermistor if you don’t see a loose or disconnected wire.T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Thermistor
    331Mixing Thermistor failureT-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Mixing Thermistor
    341Thermistor failureT-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS1. Mixing Thermistor
    2. Thermistor
    3. Output Thermistor
    4. Output Thermistor
    391Air-fuel ratio rod failure. Check wire connections and if no loose wire, replace the AFR rod.T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Not Available
    441Flow Sensor Failure (Easy-Link or Multi-Link System Only)

     

    Possible: Inlet filter clogged, water flow problem. Also check for loose wire connections.

    		T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Flow Sensor
    1. Flow Sensor
    1. Flow Sensor
    1. Flow Sensor
    1. Inlet Filter
    510Gas valve failure. Inadequate gas pressure or flow.T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Gas Valve Assembly
    2.Manifold and Gas Valve
    3. Manifold and Valve
    551Gas solenoid valve failure. Check gas supply and if no problem the solenoid needs replacement.T-H2-OS, T-M32, T-M501. Gas Valve Assembly
    2.Manifold and Gas Valve
    3. Manifold and Valve
    611Abnormal fan motorT-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Fan Motor
    2. Fan Motor
    3. Fan without pressure port
    4. Fan with pressure port
    5. Fan Motor
    621Exhaust fan motor (indoor models only)T-H2-OS1. TH2 Fan Motor
    631Pump FailureT-H2-OS, T-M32, T-M50Not Available
    651Flow Adjustment Valve Fault (Easy-Link or Multi-Link System only)T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Not Available
    661Bypass valve fault (540 (T-H3) model only)T-H2-OS, T-M32, T-M501. Non Return Valve
    681External fan motor failureT-M501. Fan Motor
    2. Fan Motor
    3. Fan without pressure port
    4. Fan with pressure port
    5. Fan Motor
    701Computer board failure; check for loose wires, electrical power supply, signs of damage to the board such as black or brown marks indicating overheating or burnedT-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Computer Circuit Board
    2. Computer Circuit Board
    3. Computer Circuit Board
    711High Limit Switch / Overheat Cutoff Fuse Circuit is Compromised

     

    Watch out: this is an unsafe condition.

    		T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS1. High Limit Switch
    721False flame detected.

     

    Check for condensate accumulation, blocked or missing condensate drain, condensate leaks.

    		T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Neutralizer Kit
    741Remote control not communicating with the water heater, check remote batteries, check remote sensor wiring, remote control access line of sight.T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M501. Remote
    2. Remote
    751Temperature Controller ProblemT-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OSNot Applicable
    761Communication Error in Easy-Link or Multi-Link System.T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Not Applicable
    941Abnormal exhaust temperature

     

    Watch out: this is an unsafe condition risking CO hazards.

    		T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OSCall For Service
    991Improper gas combustion. Abnormal combustion.

     

    Watch out: this is an unsafe condition risking CO hazards.
    If this indicator is on from first activation of the heater it may not be properly adjusted for the elevation at which the heater is installed.

    Check for blocked exhaust flue or under-sized exhaust flue.

    Check for debris clogging the gas burner or for a failed or blocked fan.

    		T-D2, T-H2-OS, T-H3-DV/OS, T-H3J-DV/OS, T-H3S-DV/OS, T-M32, T-M50Call For Service

    Takagi Models

    Interested in checking out some of the Takagi tankless water heater models? We have analyzed a few of them. Check them out.