No ice, or not enough?
Start with the number, because it settles a good share of these calls on its own: an ice maker inside a Sub-Zero freezer makes about eight cubes every two to three hours, and filling an empty bin can take one to two days. That is Sub-Zero describing normal operation, not a machine in trouble. What follows is their own list of what to check, then the faults that are left when the list runs out.
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How Much Ice Is Actually Normal
Most of the disappointment in an ice bin is a mismatch between what the machine is built to do and what a full bin looks like on a Saturday. These are Sub-Zero’s own figures.
| What to expect | Note | |
|---|---|---|
| Ice maker inside a freezer | about 8 cubes every 2–3 hours | Sub-Zero calls this normal operation |
| Undercounter ice maker | a batch roughly every 30 minutes | a different machine, a different rate |
| Filling an empty bin | 1–2 days, by model | not an overnight job |
| Freezer temperature needed | at or below 5°F | Sub-Zero recommends a 0°F setting |
| After any change | wait 24 hours before judging | the control needs a full day to settle |
A household that empties the bin faster than eight cubes every two hours is not looking at a fault; it is looking at the limit of the machine. That is a different conversation, and an honest one to have before anyone is paid to come out.
What Sub-Zero Asks You to Check
Seven checks, published by the maker, in the order they are worth doing. None of them needs a tool, and together they are most of what a first visit would do anyway.
- 01
Is the ice maker switched on?
First on Sub-Zero’s own list, and it earns the place. A control that was switched off during a clean, a power cut or a holiday will sit there cold and idle and look exactly like a failure.
- 02
Is the freezer at or below 5°F?
Sub-Zero recommends a 0°F setting. Above 5°F the ice maker’s output falls away, so a freezer that has drifted warm stops the ice long before anything in the ice maker has broken.
- 03
Is the water supply turned on?
Low pressure or no pressure prevents production outright. The valve behind or under the cabinet gets closed during plumbing work and quietly stays closed.
- 04
Is the filter past its rating?
Sub-Zero rates its own filter for 750 gallons or one year, whichever comes first, and says an inline filter in the home typically wants changing every six to twelve months. A filter well past that is an ordinary reason for ice to thin out.
- 05
Is the bin level and seated?
A bin sitting proud of its runners can hold the switch in the wrong position, and the machine behaves as though the bin were full.
- 06
Is the fill tube clear?
A fill tube frozen solid is a classic: the water arrives, freezes at the wrong point and blocks the path for everything after it.
- 07
Has the condenser been cleaned in the last six to twelve months?
Sub-Zero puts it on this list, not only on the refrigeration one. A coil that cannot shed heat drags the whole cabinet, and the ice maker is the first thing to show it. What desert dust does to a condenser.
Then wait. Sub-Zero asks for twenty-four hours to pass before checking the bin again, and that is not a formality: the control needs a full day to settle after anything is changed.
The cup-of-water test.
Sub-Zero publishes one test that needs nothing but a cup: pour water behind the ice maker curtain. If the spray changes, the unit is not getting enough water pressure. It takes thirty seconds and it separates a water problem from a machine problem before anyone is called.
There is a second check in the same spirit. If the water dispenser still runs normally, the supply into the house is fine and the fault is inside the machine. Between those two, most owners can say which side of the wall the problem is on, and that is the single most useful thing to be able to tell us on the phone.
When it is the water, not the machine.
A built-in ice machine makes clear ice by freezing water in thin layers against a chilled plate and washing away what it rejects. What it rejects is mineral, and in this valley there is a great deal of it: Phoenix published 10 to 17.6 grains per gallon in 2025, Mesa runs as high as 22, Chandler averages 16.5. The figures for each city, and what they do.
So the maintenance is not optional here. Sub-Zero asks for an undercounter ice maker to be cleaned and sanitized every six months whatever filtration is fitted, using the cleaner made for it, which is what removes limescale and calcium buildup. Not bleach. And if six months will not hold, Sub-Zero’s own answer is to have the water tested and treated rather than to clean more often forever.
What scale looks like from the kitchen is a slow slide rather than a stop: cubes get smaller, then cloudy, then hollow, and production falls off without any single component being broken. Cleaning brings that back. If it does not, the fault is downstream of the water.
What the display says.
On the Built-In 600-2 series there is one code that belongs to the ice maker: code 30, the ice maker water valve energised beyond fifteen seconds. The control is saying it called for water and the fill did not end the way it expected, which points at the valve or at what feeds it rather than at the freezing side of the machine. The full 600-2 code list.
Codes are specific to a series and a year. The rating tag inside the cabinet says which series you have, and that is what settles whether any code chart applies to your machine at all. Where the tag hides on each maker.
When something really has failed.
Work through the list above and a short set of parts is left. A fill valve furred on the inside passes less water than the cycle expects. A thickness sensor reading through a film of mineral stops the harvest at the wrong moment, so the cubes come out thin or hollow. A bin switch stops the machine with the bin still empty. A drain that no longer clears between cycles floods rather than freezes. What each of those parts does, and how it fails.
None of those is inside the sealed refrigerant circuit, which is why this is usually a shorter afternoon than an owner fears. The exception is a machine that has stopped making cold at all rather than stopped making ice, and the difference between those two is what the freezer thermometer tells you before anyone is called.
The visit is $119, waived in full when the repair goes ahead. We would rather you spent twenty minutes on the seven checks above and kept it.
Questions
How much ice should a Sub-Zero make?
An ice maker inside a freezer makes about eight cubes every two to three hours, which Sub-Zero describes as normal operation. An undercounter ice maker produces a batch roughly every thirty minutes. Depending on the model the bin can take one to two days to fill from empty, so a bin that is not full the morning after a party is not evidence of a fault.
What freezer temperature does the ice maker need?
At or below 5°F, and Sub-Zero recommends a 0°F setting. Above 5°F the ice maker’s performance falls off, so a freezer that has drifted warm will slow or stop ice production before anything in the ice maker itself has failed.
How do I know whether the water pressure is the problem?
Sub-Zero publishes a test anyone can do: pour a cup of water behind the ice maker curtain. If the spray changes, the unit is not getting enough water pressure. The other quick check is the dispenser — if the water dispenser still runs normally, the supply into the house is fine and the fault is inside the machine.
How often should the water filter be changed?
Sub-Zero rates its filter for 750 gallons or one year, whichever comes first, and says an in-home inline filter typically wants changing every six to twelve months. A filter past its rating is one of the ordinary reasons ice production falls away.
The ice maker is on and the freezer is cold, but there is still no ice.
Give it twenty-four hours after any change before judging, which is what Sub-Zero asks for, and check that the bin is level and seated and the fill tube is not blocked. If there is still no ice after a day with the freezer at or below 5°F and the water supply proven, the fault is in the machine: the fill valve, the thickness sensor, the bin switch, or the drain.
What does code 30 mean on a Sub-Zero?
On the Built-In 600-2 series, code 30 means the ice maker water valve was energised beyond fifteen seconds. The control is reporting that it asked for water and the fill did not finish the way it expected, which points at the valve or at what is feeding it rather than at the freezing side.
Sources
- Sub-Zero, ice maker does not make ice: the checklist, the freezer temperature, the water supply, the bin, the fill tube, the condenser interval and the twenty-four hour wait.
- Sub-Zero, does not make enough ice and slow ice production: eight cubes every two to three hours, the undercounter batch every thirty minutes, one to two days to fill a bin, and the cup-of-water pressure test.
- Sub-Zero, undercounter ice maker water filter: 750 gallons or one year.
- Sub-Zero, undercounter ice maker cleaning: the six-month interval whatever filtration is fitted, the cleaner rather than bleach, and testing the water when six months will not hold.
- Sub-Zero Built-In (600-2) Series technical service manual — code 30, the ice maker water valve energised beyond fifteen seconds.
- City of Phoenix 2025 Water Quality Report, City of Mesa and City of Chandler water quality pages — the hardness figures quoted above.
Written from these sources and reviewed on by Aphelion Appliance Repair, Phoenix. Rates and intervals differ by model and series; the use and care guide for yours is the one that counts. Nothing here is a manufacturer’s instruction, and work inside a sealed system is a technician’s job.
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Checked all seven, still no ice?
Tell us the model, the freezer temperature and what the cubes look like. We call you back to set a time.