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NTI · Boiler troubleshooting

Boiler bangs or hisses; Lockout 81 delta T

Trinity Tft

What is going on

Noise and delta-T trips usually mean not enough water flow.

Likely causes

  • Insufficient flow
  • Scaled or magnetite-coated heat exchanger
  • Low system pressure

Check in this order

  1. Check fuse B and the boiler pump
  2. Confirm piping matches the piping section and pressure is at least 15 PSI
  3. Descale the heat exchanger with Fernox DS-40 if scaled

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

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

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.