Why Your Ice Maker Is Producing Hollow or Undersized Ice
There's nothing worse than reaching for a cold drink and finding your ice bucket full of tiny, hollow cubes that melt in seconds. If your ice maker has suddenly started producing smaller or hollow ice instead of those solid, full-sized cubes it used to make, something is definitely off. The good news? This is almost always fixable, and the cause is usually one of a handful of common issues.
I've been repairing refrigerators for over fifteen years, and hollow ice cubes are one of the most frequent complaints I hear. Most people assume the ice maker itself is broken, but in reality, the problem usually lies upstream—with water supply, pressure, or a simple component that's gotten blocked or dirty.
Low Water Pressure or Supply Issues
The most common culprit behind small or hollow ice is insufficient water pressure reaching your ice maker. Your ice maker needs adequate water flow to fill its mold properly. If the pressure is too low, the mold fills partially, and you end up with either tiny cubes or hollow ones where the center didn't freeze solid.
Check your water line first. Walk behind or underneath your refrigerator and look at the plastic or copper water line connected to the ice maker. Is it kinked, pinched, or bent sharply? In many homes, we see lines that got caught during a move or crimped by the fridge's own weight over time. Straighten it out gently and see if that helps.
If the line looks fine, the problem might be at the source. Is your refrigerator's water shutoff valve—located where the water line connects to your home's supply—only partially open? I've found this more times than I'd like to admit. It gets nudged closed accidentally during cleaning or maintenance. Turn it fully counterclockwise to open it completely.
Clogged Water Filter
Your fridge's water filter can become clogged over time, restricting flow to both your water dispenser and ice maker. Most people remember to replace their filters every six months, but some go years without changing them. A clogged filter doesn't just affect water quality—it also reduces the water pressure reaching your ice maker.
Check how long it's been since you replaced yours. If it's been more than six months, replace it now. This is the easiest and cheapest fix you can try. When you install the new filter, run water through your dispenser for 30 seconds to purge air from the line, then check your next batch of ice.
Frozen Water Supply Line
In cold climates or if your fridge is positioned near an exterior wall, the water supply line can actually freeze, restricting water flow. This is especially common in winter or if your freezer temperature is set too low. The ice maker tries to work, but gets only a trickle of water, resulting in small or hollow cubes.
If you suspect a frozen line, you'll need to thaw it. Unplug the refrigerator, locate the water line, and apply warm (not hot) water or a heating pad to the affected section. Never use a heat gun or boiling water, as you can crack the plastic line. Once thawed, adjust your freezer temperature slightly or insulate the water line with foam tubing to prevent it from freezing again.
Issues Inside the Ice Maker Assembly
If water pressure is fine and your filter is new, the problem might be inside the ice maker itself. The fill tube that dispenses water into the mold can become clogged with mineral deposits or debris. When this happens, the mold fills incompletely, and you get undersized or hollow cubes.
This is trickier to fix yourself, as it requires accessing the ice maker assembly. You can try flushing the fill tube with warm water from a turkey baster, but if that doesn't work, the ice maker likely needs professional attention or replacement. This is also a good time to call in a refrigerator repair specialist if you're not comfortable taking the assembly apart.
Thermostat or Cycle Timing Problems
Less commonly, a faulty ice maker thermostat can cause the mold to warm up before the water fully freezes. This creates partially frozen or hollow cubes. If you've ruled out water pressure and filtration issues, the thermostat might need replacement.
Simple Steps to Get Full Ice Cubes Again
Start here: Check your water line for kinks or pinches. Verify your shutoff valve is fully open. Replace your water filter if it's been more than six months. Run water through the dispenser to purge air. Check freezer temperature—aim for 0°F, not colder. If these don't work within a few ice-making cycles, contact a professional. Most of these fixes take under ten minutes and cost nothing.
