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Rinnai · Tankless water heater

70 PC board fault

High severity Non-SENSEIRH180 hybridSENSEI RX/CXSENSEI

What the control is telling you

The control (PC) board has a fault, which may relate to incorrect parameter settings, harness connections or a failed board.

Applies to: SENSEI Series, SENSEI RX/CX Series, Non-SENSEI Series

Likely causes

  • Water heater parameters set incorrectly
  • Loose, broken or damaged harness connections at the PC board
  • Failed PC board

Test and repair steps

  1. Confirm all water heater parameters are set correctly.
  2. Inspect every harness at the PC board for loose, broken or damaged connections.
  3. Replace the PC board.
  4. SENSEI Copy data from the old board using the transfer cable supplied with the new one, or program all parameters manually per PCB Replacement Instructions (100000553).
  5. SENSEI RX/CX Copy data from the old board using the supplied transfer cable, or program all parameters manually per PCB Replacement Instructions (100000854).

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Source: Rinnai Troubleshooting TWH Diagnostic Codes (100000652), p.57. Summarized in our own words; check the original manual for your model.

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