why is my ice maker suddenly making really thin, hollow ice cubes that melt super fast?

Diagnosis

The production of thin, hollow, or "shell-like" ice cubes in the Costway EP24744US is almost always a symptom of a failure in the water-to-freeze ratio. When the ice cubes are hollow, it means the exterior of the cube froze quickly, but the core remained liquid. Because the machine's timer is based on a preset duration rather than a precise internal temperature sensor for every single cube, it ejects the ice based on the clock. If the cooling efficiency is lowered or the water volume is too high, you get a thin shell of ice that collapses and melts rapidly. The root cause is typically mineral calcification (scale) buildup on the evaporator pins. These aluminum pins are where the water freezes; when calcium and magnesium from your tap water create a crusty white layer on the pins, it acts as an insulator. This prevents the cold from penetrating the center of the cube efficiently. Additionally, if the water inlet valve is partially obstructed by scale, it can cause irregular water flow, filling the molds too full and preventing a solid freeze. You can confirm this by looking at the evaporator pins—if they look "cloudy" or have white chalky deposits instead of being shiny silver, scale is the culprit.

How to Fix It

To restore full cube density, you must perform a deep chemical descale to strip the mineral insulation from the evaporator pins and clear the internal plumbing.

1. Power down the unit and unplug it from the wall outlet to ensure the heating element for the harvest cycle doesn't engage prematurely.
2. Drain the water reservoir completely and remove any existing ice from the basket.
3. Prepare a descaling solution. While commercial descalers work, a high-concentration mixture of distilled white vinegar and warm water (1:1 ratio) is highly effective for this model.
4. Fill the reservoir to the "Max" line with the solution.
5. Plug the unit back in and press the Power button. Immediately press the Ice Size button to select the "Large" setting; this ensures the machine spends more time on the freezing cycle, allowing the solution to sit on the pins longer.
6. Let the machine run through 2 to 3 complete cycles. Do not discard the "vinegar ice"—let it freeze and eject.
7. After 3 cycles, empty the reservoir and the ice basket.
8. Fill the reservoir with fresh, filtered water and run 2 more cycles to flush out the remaining acetic acid and mineral residue.

If That Didn't Work

• Check the Ambient Temperature: If the machine is sitting in a room above 80°F (27°C) or is placed too close to a heat source (like a stove or dishwasher), the condenser coils cannot shed heat efficiently. Move the unit to a cool, well-ventilated area with at least 6 inches of clearance on all sides to improve the cooling delta.
• Adjust Water Hardness: If you are using hard tap water, the scale will return within days. Switch to bottled distilled water or a filtered pitcher. This removes the calcium carbonate that causes the hollow-cube phenomenon.
• Inspect the Cooling Fan: Locate the intake vents at the bottom and back of the unit. If dust has clogged the fan, the refrigerant cannot cool the evaporator pins. Use a can of compressed air to blow out the dust from the condenser coils and the fan motor.
• Reset the Sensor: Unplug the machine for a full 30 minutes. This allows the refrigerant to stabilize and the internal capacitors to discharge, which can sometimes resolve glitches in the timing cycle of the harvest process.

Heads Up

• Avoid Soap: Never use dish soap or detergent inside the water reservoir; it creates micro-bubbles in the ice that contribute to the hollow, "snowy" texture and can cause the pump to foam.
• Monthly Maintenance: Perform the vinegar rinse once every 30 days if you live in a hard-water area to prevent the scale from bonding permanently to the aluminum pins.
• Avoid Overfilling: Never fill the water reservoir past the maximum line, as this can cause the pump to struggle and lead to inconsistent water levels in the freezing tray.
• Refrigeration Warning: Do not store the unit in a freezer to "help it cool"; this can damage the internal coolant lines and void the warranty.