NTI · Boiler

Alert 500 Internal error: Safety shutdown

Low severity Trinity Tft

What the control is telling you

Control board logged an internal error: Safety shutdown.

Applies to: Trinity Tft60, Tft85, Tft110, Tft155, Tft175, Tft200, Tft250, Tft300, Tft399

Models that show this code

13 models in Trinity Tft

Tft110Tft154Tft155Tft175Tft200Tft201Tft250Tft285Tft300Tft340Tft399Tft60Tft85

Other codes on the same units

  • Alert 5 Invalid Factory Range PCB was detected
  • Alert 5 Invalid Factory Range PCB was detected
  • Alert 50 Maximum hours count was reached
  • Alert 50 Maximum hours count was reached
  • Alert 51 Illegal Modbus write was attempted
  • Alert 51 Illegal Modbus write was attempted
  • Alert 52 Modbus write attempt was rejected (NOT ALLOWED)
  • Alert 52 Modbus write attempt was rejected (NOT ALLOWED)

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Source: NTI Tft60-399 Installation and Operation Instructions (rev. 2012-04-09), Sec. 15.0 Troubleshooting, Table 15-4. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.