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how to turn on Sub-Zero ice maker

Troubleshooting Guide: Sub-Zero Ice Maker Not Making Ice



A lack of ice production from a high-end refrigerator or undercounter ice maker can leave you without a convenient amenity. Why is your Sub-Zero ice maker not making ice? A freezer temperature that’s too high can hamper its performance. Troubleshoot an ice maker that doesn’t produce ice with these common causes.

Sub-Zero Ice Maker Not Making Ice?
This May Be Why.

Usually, a Sub-Zero ice maker not making ice has a straightforward cause and simple solution. From a warm freezer temperature to ice jam obstructions, here’s how to determine the problem.

Ice Maker is Turned Off

If the ice maker isn’t powered on, it won’t be able to produce ice. Wondering how to turn on Sub-Zero ice maker? Most can be turned on via an ice maker button on the refrigerator or freezer control panel. Once on, the word ICE or an image of ice cubes should appear on the control panel display. Refer to your user manual for instructions specific to your model refrigerator. It may take up to 24 hours for a refrigerator ice maker to produce ice once it’s turned on.

To turn on undercounter ice makers, press the POWER button on the control panel. A green light should illuminate, indicating that the unit is on.

Freezer Temperature is Too High

A freezer or ambient temperature that’s too high is too warm to support ice production. For optimal ice production make sure your Sub-Zero freezer temperature setting is 0℉. Depending on your model refrigerator, the freezer temperature can be adjusted via the electronic control panel or a temperature dial. For those models with a temperature dial, set it between 4 and 6 to keep the freezer at 0℉. Undercounter ice makers must remain in a room where the ambient temperature stays below 100℉ to function properly.

If your Sub-Zero refrigerator isn’t cold and the freezer feels warm despite the right temperature setting, the condenser coils may need a cleaning. Dirty condenser coils may not sufficiently cool the refrigerant, limiting the production of cold air. Most coils are located behind a front grille and can be easily cleaned with a vacuum’s brush attachment or appliance brush.

Sub-Zero water filter

Image Courtesy of Sub-Zero

Sub-Zero Ice Maker is Jammed

Is your Sub-Zero ice maker freezing up from ice jams? These obstructions occur during ice production when liquid water collects on ice maker components and freezes, blocking ice from reaching the ice bin. If the blockage can’t be removed by hand, it can be melted by manually defrosting the freezer. Refer to your user manual to determine the right defrosting process for your model refrigerator. Some models enable a manual defrost of the freezer while maintaining power to the refrigerator.

Low Water Pressure

Low water pressure restricts the ice maker’s water supply, limiting ice production on both refrigerator and undercounter models. The refrigerator has a water inlet valve that opens and closes, allowing water to flow to the refrigerator from your home supply. This valve requires either 20-100 or 35-120 psi of pressure, depending on your model refrigerator. If the pressure is too low, the valve may not open to supply the ice maker with water. 

A plumber should assess your home’s water pressure if the kitchen sink exhibits low water flow and you can’t adjust the pressure yourself. 

Frozen Ice Maker Fill Tube

The ice maker’s fill tube supplies it with water from your home’s supply after it’s been filtered by the Sub-Zero water filter. This tube can be found on the back or side wall of the freezer, above the ice maker. Sometimes, residual water droplets inside the fill tube or Sub-Zero ice maker water line freeze, restricting water flow. This is more likely to occur when there is low water pressure to the water inlet valve. When this happens, you’ll find your Sub-Zero ice maker not making ice due to a lack of water supply. Sub-Zero recommends manually defrosting the freezer to melt the fill tube obstruction.

Don’t let a Sub-Zero ice maker not making ice keep you from enjoying the amenities of this high-quality appliance. Contact RD Appliance Service, Corp for a fast and professional ice maker repair!

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