Cleaning a commercial ice machine takes two separate products in order: a descaler to strip mineral buildup off the evaporator, then a sanitizer to remove the algae and slime growing on the surfaces the ice touches. The two are not interchangeable. Hoshizaki and Manitowoc both set the interval at every six months, and Manitowoc adds that cleaning more often than every two months should be avoided. That interval carries legal weight, because the FDA Food Code treats ice as a food and requires ice makers to be cleaned at the frequency the manufacturer specifies.
Key facts
- Ice is legally a food under the FDA Food Code, so an ice machine is food equipment a health inspector can cite (Food Code 2022, 4-602.11(E)(4)).
- The CDC linked 46 Burkholderia multivorans infections to hospital ice and water machines across four hospitals, 2020 to 2024 (CDC MMWR 73(39)).
- Manufacturers set the cleaning interval, and Hoshizaki and Manitowoc both specify every six months.
- Cleaning needs two products in order: a descaler for mineral scale, then a sanitizer for algae, slime and biofilm.
Before you start, it pays to know what you are actually looking at. Operators call almost anything growing inside the machine “mold,” and most of the time it isn’t.
| What you see | What it usually is | What it means |
|---|---|---|
| Pink, orange or red film | Bacteria. Serratia species produce a red pigment and are common in water systems | Biofilm has taken hold. Needs the sanitizer step as well as descaler |
| Black or dark green specks | Mold or yeast, often from airborne kitchen sources | Same treatment, and check the air filter and surroundings |
| Clear or gray slime | Mixed biofilm, bacteria and yeast together | The machine is overdue |
| White or chalky crust | Mineral scale from the water supply | Descaler step, and look at water filtration |
How do you clean a commercial ice machine, step by step?
Descaler first, sanitizer second. The two products do different jobs, and sanitizer cannot reach scale, so the order is not optional. Work through it like this:
- Empty the bin and discard the ice. Any ice made before or during the clean gets thrown out.
- Start the machine’s cleaning cycle the way your manual directs, or shut it down and open it up if the model has no cycle.
- Take out the removable parts, the water curtain, distribution tube and bin components, so you can reach the seams where growth hides.
- Run the manufacturer’s descaler if there is visible lime scale, following the concentration and contact time on the label. Skip it if there is no scale to remove.
- Rinse the descaler off with clean water.
- Apply the manufacturer’s sanitizer to the food-contact surfaces and the parts you removed, following the label. Ice machine sanitizers are usually left on, not rinsed off, but the label is the authority.
- Reassemble, then run a cycle and discard the first batch of ice.
Use a soft nylon brush, a sponge or a cloth on the surfaces the ice touches. Metal brushes, steel wool and abrasive pads scratch the plating and give biofilm more to hold onto. Many machines print the model-specific steps on a label inside the front or side panel, so check there before you start.
Do commercial ice machines need to be cleaned?
Yes, and it is a code requirement rather than a recommendation. The FDA Food Code defines food to include ice outright. The definition reads: “Food means a raw, cooked, or processed edible substance, ice, BEVERAGE, or ingredient used or intended for use or for sale in whole or in part for human consumption, or chewing gum.” Section 3-202.16 adds that ice for use as food or as a cooling medium has to be made from drinking water.
Because ice is a food, the machine that makes it is food equipment. Section 4-602.11(E)(4) names it directly, covering ice bins, beverage dispensing nozzles, and enclosed components of equipment such as ice makers. Those have to be cleaned “(a) At a frequency specified by the manufacturer, or (b) Absent manufacturer specifications, at a frequency necessary to preclude accumulation of soil or mold.”
That wording carries two consequences. The manufacturer’s interval is the standard a health inspector measures you against, and the code uses the word mold explicitly, so visible growth is not a gray area during an inspection.
How often does a commercial ice machine need to be cleaned?
Every six months, and the two largest manufacturers agree on it. Hoshizaki’s service manual lists the appliance and ice storage bin under “Every 6 Months” for cleaning and sanitizing. Manitowoc gives the same interval for its cleaner and says sanitizer is needed “a minimum of once every six months.”
There is a lower bound too, which almost nobody mentions. Manitowoc states that a cleaning frequency “shorter than two months must be avoided” and that ice machine cleaner “must not be used on a weekly or monthly basis.” Descaler is only called for when there is visible lime scale on the evaporator or other parts. Running descaler when there is no scale to remove leaves the acid working on the metal for nothing.
Clean more often than six months when conditions call for it:
- Bakeries. Manitowoc names this directly. In areas with a high concentration of airborne yeast, such as bakeries, more frequent sanitizing will be required.
- Fryer-heavy kitchens. Airborne grease coats the air filter and the condenser, which makes the machine run hotter.
- Hard water. Scale builds faster and insulates the evaporator, so the machine runs longer for the same amount of ice.
- Heavily scaled flake and nugget machines. For those, Manitowoc recommends a preventive cleaning or sanitizing every 30 days alongside the standard six-month service.
One more interval belongs on the same schedule. Manitowoc says to clean the condenser at least every six months. It never touches ice, but a blocked one raises the operating temperature across the whole machine. On an air-cooled machine an operator can brush or vacuum the finned condenser and clean the air filter. A water-cooled condenser scales up on the inside and usually needs a technician to descale, which is not a job to improvise.
Check your own manual before settling on an interval. Hoshizaki, Manitowoc, Scotsman and Ice-O-Matic each publish schedules by model, and a flaker does not have the same schedule as a cuber.
It also matters who the manufacturer expects to do this. Hoshizaki puts the six-month clean and sanitize in its service maintenance schedule, the one it says is to be performed by qualified service technicians only. The bi-weekly air filter check and the monthly wipe-down sit in the user schedule.
What can you clean a commercial ice machine with?
Two products, used in order, because they do two separate jobs. A descaler dissolves lime scale and mineral deposits. A sanitizer removes algae and slime and disinfects. Manitowoc puts it plainly in its service manual: use sanitizer to remove algae or slime, and do not use it to remove lime scale or other mineral deposits.
The order matters. Scale is a hard barrier, and sanitizer cannot reach what is underneath it. Descale first, rinse, then sanitize.
Use the products your manufacturer specifies. Manitowoc’s warning is that using a non-Manitowoc descaler or sanitizer “may result in bodily harm and/or cause damage to the ice machine that is not covered under the warranty.” Ice machine descalers are acid based by design, and Manitowoc’s contains citric and phosphoric acid, at a concentration the machine’s metals are built to take. Some machines use nickel-plated evaporators that call for a nickel-safe cleaner, which is milder than a standard descaler, so match the cleaner to what your manual specifies. A general kitchen degreaser or a slug of bleach in the sump is a different thing entirely.
A full clean also means taking out the removable parts, the water curtain, distribution tube and bin components, and cleaning them separately. Growth hides in the seams and along the curtain, where wiping the flat surfaces will never reach it.
Can you run vinegar through your ice machine to clean it?
No, and the reason is more specific than acid being bad for the machine. Purpose-made ice machine descalers are acid based themselves; the Manitowoc descaler from the last section is built on citric and phosphoric acid. The difference is that it is formulated for the equipment, at a controlled concentration, with published contact times and a rinse procedure.
Vinegar fails on the part that matters most. It does not sanitize. It has some effect on light scale, which is why the advice keeps circulating, but algae, slime and biofilm need a product sold as a sanitizer, and vinegar is not one. Run vinegar through the machine and you have skipped the sanitizing step while believing the machine is clean.
There is a warranty problem as well. Manitowoc is explicit that using a cleaner other than its own can void warranty coverage. That is worth confirming before improvising with what is under the bar sink.
The advice is everywhere online because most of it is written for countertop ice makers in home kitchens. A commercial machine uses different metals and carries its own warranty.
How do you clean mold out of a commercial ice maker?
Cleaning mold out of a commercial ice maker uses the same two steps, descaler then sanitizer, with attention to where growth actually starts. What most people call mold is usually biofilm, a mixed layer of bacteria, yeast and fungi. Pink or red film is characteristically bacterial rather than fungal; that red pigment is usually Serratia, a bacterium at home wherever water sits.
The practical difference is that biofilm is anchored to the surface, not floating in the water. Wiping does not remove it, and sanitizer alone struggles to penetrate it. That is why growth returns within days of a quick wipe: the wipe never reached what was holding it.
A few spots read clean but are not, and they are where our technicians find growth most often:
- The water curtain and its seams, where growth gets a foothold out of sight
- The distribution tube, especially the small holes
- The bin, including the door gasket and the drain
- The drain pan. CDC investigators isolated the outbreak strain from the drain pans of two machines in a documented hospital outbreak
- The air filter and condenser, which do not touch ice but govern how hot the machine runs
Can a dirty ice machine make people sick?
Yes, a dirty commercial ice machine can make people sick, and there is documented evidence. Two things are certain and one is documented. Keep them separate.
Certain: it is a health-code violation. Ice is a food, the Food Code names ice makers, and the word mold is in the requirement.
Certain: it costs you production and equipment. Scale and biofilm insulate the evaporator, so the machine runs longer, makes less ice and wears harder.
Documented: ice machines have caused infections. In a 2024 report, CDC described 46 cases of Burkholderia multivorans linked to ice and water from ice machines across four hospitals in California and Colorado between 2020 and 2024. The organism was isolated from ice, water and the drain pans of two machines, and the hospitals pulled every affected machine from service. That investigation involved hospital patients, including immunocompromised people, so it does not transfer directly to a restaurant dining room. It is the clearest evidence available that the machine itself can be the source.
Separately, CDC has noted that “clean ice that becomes contaminated has been implicated in outbreaks involving norovirus, Cryptosporidium, and E. coli.”
For most commercial kitchens the realistic outcome of a neglected machine is a failed inspection, a bin of ice in the trash and a service call, rather than an outbreak. That is reason enough to keep the interval.
What if it keeps coming back?
Growth that returns within weeks of a proper clean is a sign that something is feeding it, and the answer is upstream of the cleaning schedule. Work through these:
- Water quality and filtration. A spent filter stops doing anything. Filters are rated by gallons as well as by months, and a high-volume machine reaches the gallon limit early.
- Air filter and condenser. A blocked condenser makes the machine run warmer, and warmer machines foul faster.
- Heat and clearance. A machine wedged into a hot corner with no clearance runs hotter than its rating assumes.
- The drain. A slow or partially blocked drain leaves standing water, which is where biofilm starts.
- Airborne contamination. Yeast from baking or flour, or grease from frying, keeps reseeding a machine no matter how well it was cleaned.
When does this stop being a cleaning job?
When the fix requires opening the sealed system or working on live electrical components. Cleaning is maintenance and an operator or a kitchen team can carry it out. The following are not cleaning problems:
- The machine is not making ice, or production has dropped noticeably after a clean
- Ice is forming but not releasing from the evaporator
- The evaporator plating is visibly pitted, flaking or discolored under the scale
- Water is leaking, or the drain will not clear
- The machine short cycles, freezes up, or trips a breaker
- Refrigerant work of any kind
Those need a refrigeration technician. Continuing to run a machine with a pitted evaporator or a sealed-system fault turns a repair into a replacement.
Common questions
How long does a full clean take?
Budget two to three hours for a typical cuber, including draining the bin, the descaler cycle, the sanitizer cycle, cleaning the removable parts and letting the machine make and discard the first batch of ice.
Do I have to throw out the ice already in the bin?
Yes. Empty the bin before you start, and Manitowoc’s manual also requires that all ice produced during the cleaning and sanitizing procedures be discarded.
Does a water filter mean I can clean less often?
No. Filtration reduces scale and improves ice quality, but it does not stop biofilm and it does not change the manufacturer’s interval.
Can I use any ice machine cleaner, or does it have to be the manufacturer’s?
Use what your manufacturer specifies. Manitowoc warns that an off-brand descaler or sanitizer can void warranty coverage, and the manufacturer sets concentration and contact time for that machine’s metals.
Who is responsible for cleaning under a health inspection?
The operator. The Food Code sets the requirement against the establishment, and the manufacturer’s published interval is the benchmark.
If the machine needs more than a clean
ProToCall handles commercial ice machine repair for restaurants, bars, hotels and healthcare facilities across eight states, with our own technicians. If your machine has stopped producing, is not releasing ice, or has a fault a clean will not fix, call 866-297-5082 to schedule a service visit and a technician will diagnose it on site.
To keep commercial ice machine cleaning and service on a fixed schedule, ProCare 360 tracks the intervals and handles the visits. Our guide to commercial ice machine maintenance covers what to watch for between visits.
Image: Manitowoc Q210 commercial ice machine by BrokenSphere / Wikimedia Commons, CC BY-SA 3.0.