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john_117 Member Posts: 15
On a Knight WHN-155 what does the S2 lockout indicate?


  • icesailor
    icesailor Member Posts: 7,265
    The installer should have left the I/O manual for the boiler with the boiler. In that manual are printed the codes and what they mean from the manufacturer.
  • SWEI
    SWEI Member Posts: 7,356
    S2 is the inlet sensor. The errors I have seen on the WH controls are in plain English (nice, actually.)
  • john_117
    john_117 Member Posts: 15
    ok thanks guys.