HVACopedia

NTI · Boiler troubleshooting

Replace the main PCB

TRX150

What is going on

New main board on the TRX150. Swap it, then set the parameters from the kit sheet. Skip that and it will not run right.

Likely causes

  • Failed controller board, dead display or no response
  • Board damaged by moisture or a power surge
  • Parameters left at defaults after the swap

Check in this order

  1. Power off first. Fold down the electronics box.
  2. Unlock the two clips and open the electronics box cover.
  3. Disconnect the electrical connections, noting where each goes.
  4. Unhook the controller board and remove it.
  5. Install the new PCB in reverse order.
  6. Set all required parameters following the replacement kit instructions.
  7. Run a full call for heat and confirm normal operation.

Applies to: TRX150

More boiler guides

Related

NTI error codes · NTI parts · NTI tips · Calculators and reference tables

Take it to the job

All guides, error codes and tips work offline in the HVACopedia app.

Open the app

Source: NTI TRX150 manual, p. 100. 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.