Takagi Water Heater Error Code 24: How to Fix It

Q: What does error code 24 mean on a Takagi water heater?

Error code 24 on a Takagi tankless water heater indicates a servo motor fault. The servo motor is responsible for modulating the gas valve to control the burner flame and water temperature. When the unit detects that the servo motor is not responding correctly or has failed, it shuts down and displays code 24 to prevent unsafe operation.

Q: Can I reset error code 24 on my Takagi water heater myself?

Yes, you can attempt a reset by powering the unit off for 60 seconds and then restoring power. If the code was triggered by a temporary voltage fluctuation or communication glitch, the reset may clear it. However, if error code 24 returns after 2-3 resets, there is an underlying hardware issue — such as a failed servo motor or damaged wiring — that requires further diagnosis and repair.

Q: How much does it cost to fix a Takagi error code 24?

If only a wiring connection needs to be re-seated, the repair may cost nothing. A replacement servo motor part typically costs between $50 and $200 depending on your Takagi model. If you hire a licensed plumber or technician, expect to pay an additional $100 to $250 in labor. If the control board is at fault, parts and labor combined can range from $200 to $500 or more.

Q: Is it safe to use my Takagi water heater while it shows error code 24?

No. When error code 24 is active, the Takagi unit will shut down and refuse to operate as a built-in safety measure. You should not attempt to bypass this fault. The servo motor controls gas valve modulation, and running the unit with a faulty servo motor could result in improper combustion, overheating, or gas-related hazards.

Q: How long does a Takagi servo motor last?

Servo motors in tankless water heaters typically last 10 to 15 years under normal operating conditions. Premature failure can be caused by moisture intrusion inside the unit, power surges, excessive cycling, or manufacturing defects. Regular annual maintenance — including inspecting internal wiring and flushing the heat exchanger — can help extend the lifespan of all internal components, including the servo motor.

Abstract

Takagi error code 24 indicates a servo motor fault in your tankless water heater. The servo motor controls the gas valve modulation, which regulates the flame to maintain your desired water temperature — when it fails or loses communication, the unit shuts down as a safety measure. This error can be caused by a faulty servo motor, wiring issues, or a problem with the control board sending signals to the motor.