Portable AC displays P4 and stops operation.

Safety: Unplug the unit before inspecting the exhaust system.

Steps:

• Check exhaust hose: Ensure the hose is not crushed, kinked, or excessively long. Straighten and shorten if necessary.
• Inspect window kit: Make sure the exhaust outlet is not blocked by covers, insects, or debris.
• Relocate unit: Maintain adequate clearance around the unit (at least 30 cm from walls) for proper air intake.
• Clean condenser intake filter: If your model has a separate rear filter for condenser air, clean it thoroughly.

If P4 persists, the internal temperature sensor or control board may require service.