Takagi Error Code 200: Overheating

Severity
Warning
Type
digital display
Estimated repair cost: $75 — $200 (parts + labor)
Warning: The water heater has shut down due to overheating. You likely have no hot water. Resetting *might* restore function, but the underlying problem needs diagnosis.

How to Fix Takagi Code 200

  1. Step 1: Check that all hot water taps are fully closed. A small drip can trigger the heater unnecessarily.
  2. Step 2: Ensure the water supply valve to the unit is fully open.
  3. Step 3: Press the reset button on the unit. If the error reappears shortly after, call a qualified technician.

How to Reset Takagi Code 200

  1. Turn off the unit using the power button on the front panel.
  2. Turn off the gas supply valve.
  3. Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
  4. Restore power at the breaker, then open the gas valve.
  5. Turn the unit back on. If the error returns, the underlying issue needs repair.

What does 200 mean?

The Takagi error code 200 indicates the unit's high limit switch has tripped, meaning the water temperature exceeded its maximum safety threshold. This shuts down the burner to prevent damage and potential scalding. Several things can cause this, but it usually points to a problem with water flow, burner operation, or a faulty sensor. The unit is designed to protect itself, so it's important to figure out why it's overheating instead of repeatedly resetting it.

When this happens, the heater stops producing hot water, and you'll see the 200 error code displayed. The unit will likely lock out and require a manual reset. While a temporary reset might restore hot water, the underlying issue will likely cause the problem to reoccur. Ignoring this error can lead to further damage to the unit or even create a safety hazard.

Affected Models

Replacement Parts

PartOEM NumberEst. Cost
High Limit Switch TK5000500 —
Flow Sensor TK5000300 —
Thermistor — —

Related Codes on Same Models

CodeDescriptionSeverity
101 Combustion Abnormality Critical
111 Ignition Failure Critical
121 Flame Failure Critical
207 Bypass Valve Error Warning
291 Flow Rate Issue Warning
312 Outlet Temp Sensor Warning
321 Inlet Temp Sensor Warning
391 Exhaust Temp Sensor Warning
510 Gas Solenoid Valve Critical
610 Fan Motor Fault Warning