it's not cooling my room evenly, just the area right in front of it. is it underpowered or broken?

Diagnosis

The issue you are experiencing with your Costway EP24618US is not a mechanical failure or a broken compressor, but rather a fundamental limitation of single-hose portable air conditioner design known as "negative pressure." Because the unit sucks warm air from the room to cool the condenser coils and then blasts that hot air out through the exhaust hose, it is effectively removing air from your room. This creates a vacuum effect that forces warm air from other rooms, hallways, or outside gaps to be sucked into your space to replace the displaced air. Consequently, you get a "cold zone" directly in front of the louvers, but the rest of the room remains warm because the unit is fighting a constant influx of outside heat. If you feel a draft coming from under your bedroom door or through window frames while the AC is running, this confirms the negative pressure cycle is occurring. The unit is likely performing at its rated 14,000 BTU capacity, but the air distribution is inefficient due to the physics of the single-hose system.

How to Fix It

To overcome the localized cooling effect and distribute the air evenly, you must implement a forced-air circulation strategy and seal the environment. Follow these exact steps:

1. Optimize Louver Positioning: Set the swing function to "Auto" or manually adjust the horizontal louvers to point slightly upward. Cold air is denser than warm air and will naturally sink; by pointing the air toward the ceiling, you allow it to drop gradually across the room rather than pooling on the floor immediately in front of the unit.
2. Implement a Circulation Bridge: Place a 16-inch or 20-inch high-velocity box fan approximately 3 to 5 feet in front of the AC unit. Do not point the fan toward the AC; instead, point it toward the furthest corner of the room. This "grabs" the cold air pocket and pushes it into the stagnant areas of the room.
3. Seal the Exhaust Interface: Check the window slider kit. Use weatherstripping foam or duct tape to seal any gaps around the plastic window adapter. If air is leaking in around the hose, the AC is simply cooling the air it just sucked in from outside.
4. Minimize Infiltration: Close the door to the room and place a "draft stopper" or a rolled-up towel at the base of the door. This prevents the negative pressure from pulling warm air from the rest of the house into your cooled zone.
5. Clear the Intake: Ensure there is at least 20 inches of clear space around the back and sides of the unit. If the intake filters are blocked by curtains or furniture, the airflow volume drops, reducing the "throw" distance of the cold air.

If That Didn't Work

• Deep Clean the Evaporator Coils: Dust buildup on the internal coils can reduce heat exchange efficiency, meaning the air coming out isn't cold enough to travel far. Unplug the unit, remove the washable filters, and use a vacuum with a soft brush attachment to gently remove dust from the aluminum fins. If they are greasy, use a specialized no-rinse coil cleaner spray.
• Shorten the Exhaust Hose: If you have extended the exhaust hose using third-party extensions, remove them. The EP24618US is designed for a specific hose length; extending it increases backpressure and heat radiation from the hose itself, which warms the room while the AC is trying to cool it.
• Evaluate Room Volume vs. BTU: While 14,000 BTU is powerful, it is rated for a specific square footage (typically up to 550 sq ft). If your room has vaulted ceilings or large south-facing windows without blackout curtains, the "solar load" may exceed the unit's capacity, making the cooling feel localized because the walls are radiating heat faster than the AC can cool the air.
• Check the Refrigerant Charge: If the air coming out of the vent is only "cool" (around 60-65°F) rather than "cold" (45-55°F), you may have a slow refrigerant leak. Use a digital probe thermometer at the vent; if the delta between the room temp and vent temp is less than 15 degrees, the unit may require professional servicing.

Heads Up

• Filter Maintenance: Clean the intake filters every two weeks during peak summer. Clogged filters reduce CFM (cubic feet per minute) of airflow, which directly causes the "cold spot" effect.
• Hose Insulation: The exhaust hose gets extremely hot and acts like a radiator. Wrap the hose in a reflective insulating sleeve or bubble wrap to prevent it from heating the room it is trying to cool.
• Avoid "Turbo" Overuse: Running the unit on the highest fan speed constantly can sometimes create a "wind tunnel" effect that pushes air too fast to mix, actually worsening the uneven cooling. Try the medium setting for better air blending.
• Drainage Check: Ensure the internal condensate tank isn't nearly full. When the water level is high, some models reduce efficiency or trigger an auto-shutoff, which can lead to intermittent cooling cycles.