Hisense Hi-Ultra Xtreme code 16 changes with operating mode

What Does Error 16 Mean?

On the documented Hisense Hi-Ultra Xtreme 454B family, code 16 is mode-dependent: in cooling it reports indoor-coil antifreeze protection, while in heating it reports an overload protection condition. Record the active mode because the same number leads to a different diagnostic branch. Applies to: Hi-Ultra Xtreme R-454B This dual meaning belongs to the Hi-Ultra Xtreme R-454B service literature cited here. It must not be applied to Hisense portable appliances, dehumidifiers, other refrigerants, or unrelated ductless series. Owner-safe checks: Preserve the active mode, photograph code 16, inspect only accessible filters and clearances, and let visible ice thaw without tools or added heat. Qualified technician: Sensor, fan, refrigerant, pressure, wiring, and control-board tests require a technician using the Hi-Ultra Xtreme 454B service procedure.