Indoor unit displays F8 and the unit may run at reduced capacity or shut down in extreme conditions.

Safety first: No internal high-voltage work is typically required for this code, but always turn off power before opening panels.

• Step 1 – Check ambient conditions:
  • Verify that the outdoor temperature is within the operating range specified in the Hisense manual for cooling or heating.
• Step 2 – Inspect ambient sensor:
  • Locate the outdoor ambient sensor (often near the air intake grille).
  • Ensure it is not directly exposed to artificial heat or cold sources (e.g., exhaust vents).
• Step 3 – Technician diagnosis: If F8 appears at normal ambient temperatures, a technician should test the ambient sensor and replace it or the outdoor PCB as needed.