Portable Hisense air conditioner displays P4 and stops cooling.

Safety first: Unplug the unit before moving or cleaning it.

• Step 1 – Check exhaust hose:
  • Ensure the hose is not kinked, crushed, or longer than recommended.
  • Verify the window kit is installed correctly and hot air is vented outside.
• Step 2 – Improve ventilation:
  • Move the unit at least 30 cm away from walls or furniture.
• Step 3 – Clean condenser intake:
  • Vacuum dust from the rear grille and clean filters.
• Step 4 – Cool-down period:
  • Allow the unit to rest for 30 minutes before restarting.
• Step 5 – Technician check: If P4 recurs, internal temperature sensors or compressor protection circuits may need professional diagnosis.