A refrigerator ice maker works on a simple loop. It fills the mold with a shot of water, waits for the cubes to freeze through, then pushes or twists them out and starts again. When the cubes start coming out undersized, as thin slivers, or hollow in the middle, the freezing side is seldom the problem. Far more often the mold is not getting enough water, and the reason sits somewhere between the ice maker and the valve at the wall.
Small cubes mean a short fill
Most ice makers do not measure water by volume. They open the inlet valve for a set number of seconds and count on household pressure to deliver the right amount. Anything that slows the flow shortens every fill, and the cubes shrink to match. The first suspects depend a lot on when your house was built.
Older houses: the saddle valve
In Mountlake Terrace 44% of homes date from 1950 to 1969. Shoreline and Lake Forest Park each have about a third of their homes built before 1960, and roughly 40% of Lynnwood's went up in the 1960s and 1970s. Those kitchens were not planned around an ice maker. When one was added later, the quick way to get water to it was a saddle valve: a clamp on a copper pipe under the sink or in the crawl space, with a needle that pierces the pipe. Over the years the tiny hole it made narrows with corrosion and debris, or the needle was only partly backed out to begin with. The flow drops a little at a time, and the cubes shrink with it.
The thin plastic tubing that often runs from a saddle valve to the fridge has its own weak points. It kinks behind the refrigerator, gets pinched under a cabinet base, and turns brittle with age. Replacing a saddle valve and old tubing with a proper quarter-turn valve and a braided line is a small plumbing job that fixes the flow for good.
Newer townhomes: the valve box
The townhomes and apartments built near the Lynnwood City Center, Mountlake Terrace and Shoreline light-rail stations take the opposite approach. The fridge supply comes from a recessed box in the wall behind the refrigerator, with its own small shutoff. Those valves are sometimes left partly closed after construction or a move, and the line from the box kinks when the refrigerator is pushed back into a tight alcove. A fridge that made full cubes in its old kitchen and small ones after the move to a new townhome usually has a supply problem, not an ice maker problem.
Filter, inlet valve and pressure
- Water filter. An overdue filter is the most common cause of a slow fill. So is a replacement that is not fully seated or does not quite match the housing. Change it on schedule, and run a few glasses through the dispenser afterward to push out the trapped air.
- Inlet valve screen. The valve on the back of the refrigerator has a fine screen where the supply line connects. With water as soft as the Everett supply, heavy mineral scale is less likely here than in hard-water regions; grit from plumbing work or a water-main repair is the more likely clog.
- The valve itself. A valve whose ice-maker side opens weakly shortens every fill even when the dispenser seems fine. We test its coil and its flow before replacing it.
- Household pressure. Homes on a slope, from the Edmonds bowl up toward Five Corners to the hills above Richmond Beach, can see different pressure from their neighbors. A pressure-reducing valve where the water enters the house can also fail low. If every faucet seems weak, the fridge is not the place to start.
A quick comparison helps. Fill a measuring cup from the dispenser and note how long it takes, then repeat after the next filter change. If the dispenser is slow too, the restriction is upstream, in the filter, the line or the wall valve. If the dispenser runs strong but the cubes are still small, the ice-maker side of the valve or the fill tube is the likelier spot.
Hollow cubes and clumps in the bin
Hollow cubes are a different fault. The outside of the cube freezes, the ice maker harvests before the center has finished, and the water inside spills into the bin, where it glues the cubes into a block. The usual cause is a mold thermostat or sensor that signals too early, or an ice maker control that has started misjudging the cycle. Your technician checks the freezer temperature first, since a freezer far off its setting throws off every other reading, then tests the sensor and the ice maker module.
What we work on
Ice makers built into the refrigerator or freezer are ours: modules, inlet valves, sensors, fill tubes, auger motors and dispensers in Whirlpool, KitchenAid, GE, LG, Frigidaire and Bosch refrigerators, among others. If the ice maker is fine and the refrigerator itself has a refrigerant problem, we tell you on the spot, since we don't do sealed-system work, and help you decide what to do next.
Call (425) 287-5458 or book online, and type the refrigerator's model number into the form if you have it handy. The $95 diagnostic is credited toward the repair once you approve the written estimate. Ice maker repairs start at $289, which marks where the category begins rather than quoting your repair; the exact number comes on the estimate after we find the cause. More on ice maker repair.