If your JennAir ice maker is producing less ice than expected or making smaller cubes, several factors could be responsible. This guide covers diagnosis and solutions.
Expected Production vs. Actual Production
JennAir undercounter ice makers are rated for a specific daily ice production under ideal conditions — typically 70 degrees Fahrenheit ambient temperature and 50 degrees Fahrenheit incoming water temperature. In real-world conditions, production is usually 10 to 25 percent lower than the rated capacity. However, if production drops significantly below what you normally experience, or ice cubes are noticeably smaller or thinner than usual, something needs attention.
Check 1: Water Supply
- Water pressure — the ice maker requires at least 20 psi water pressure to fill properly. Low water pressure produces thin or undersized cubes because the water trough does not fill completely before the freeze cycle begins.
- Supply valve position — ensure the water supply shut-off valve is fully open. A partially closed valve restricts flow.
- Kinked supply line — check the braided supply line for kinks or crimps, especially if the unit was recently moved or serviced.
- Clogged water filter — if your ice maker has an inline water filter, a clogged filter restricts flow. Replace it per the manufacturer’s schedule (typically every six months).
Check 2: Ambient Temperature
Ice production is directly affected by the room temperature where the ice maker is installed:
- In rooms above 80 degrees Fahrenheit, the condenser works harder and ice production drops significantly.
- Ensure the ice maker has adequate ventilation — the condenser expels heat and needs airflow. If the unit is enclosed in cabinetry, the toe-kick grille must be unobstructed.
- Avoid placing the ice maker near heat sources like ovens, dishwashers, or direct sunlight.
Check 3: Condenser Condition
A dirty condenser is one of the most common causes of reduced ice production. When the condenser coils are covered in dust and lint, the refrigeration system cannot dissipate heat efficiently, and the compressor runs longer with less cooling effect.
- Unplug the unit.
- Remove the front grille or access panel.
- Brush and vacuum the condenser coils.
- Restore power and monitor production over the next 24 hours.
Check 4: Scale Buildup on Evaporator
Mineral scale from hard water gradually coats the evaporator plate where ice forms. Scale insulates the plate, making it harder for ice to freeze and causing thinner or misshapen cubes. Run a cleaning cycle with an ice machine descaler to remove the buildup. In hard water areas, this should be done every three months.
Check 5: Mechanical Issues
- Harvest cycle timing — if the ice maker harvests (drops ice from the evaporator) too soon, cubes will be small. If it harvests too late, cubes may be too thick or the cycle takes too long. The control board manages harvest timing — if it is consistently off, the board or the ice thickness sensor may need recalibration or replacement.
- Low refrigerant — a sealed system leak causes the evaporator to not get cold enough. You may notice frost patterns on only part of the evaporator. This requires a certified refrigeration technician.
- Failing compressor — if the compressor runs but the evaporator does not reach freezing temperature, the compressor may be weak. A technician can test this with gauges.