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Rinnai · Tankless water heater

21 PC board data transfer error

High severity SENSEI RX/CXSENSEI

What the control is telling you

Data/parameter transfer to a PC board (typically a replacement board) did not complete correctly.

Applies to: SENSEI Series; SENSEI RX/CX Series

Likely causes

  • Data transfer incomplete after PC board replacement
  • Parameters not programmed correctly for the model
  • Board replacement/data transfer instructions not followed
  • Gas valve parameters missing or wrong (SENSEI RX/CX)

Test and repair steps

  1. If the PC board was replaced, confirm the data transfer process finished.
  2. Confirm all parameters match the water heater model installed.
  3. Confirm the data transfer instructions were followed during board installation.
  4. SENSEI If transfer failed, manually program all 14 parameters per the PC Board Replacement Instructions shipped with the new board.
  5. SENSEI RX/CX If transfer failed, enter the gas valve parameters correctly per the Gas Valve Replacement Instructions (100000855) or PCB Replacement Instructions (100000854).

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Source: Rinnai Troubleshooting TWH Diagnostic Codes (100000652), p.32. Summarized in our own words; check the original manual for your model.

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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.