Ice machine water filters: what they do, which kind, and when to change them
By Vimal Bhaya, Founder and Lead Systems Architect · Last reviewed 5 November 2026
This is a continuation of Commercial ice machine maintenance, a 5-part tutorial. You are on part 3 of 5.
An ice machine water filter does up to three jobs: it catches sediment, its carbon takes out chlorine taste and smell, and a scale inhibitor keeps minerals dissolved, so less scale forms on the plate. Change the cartridge on its date or its gallons, whichever comes first.
Six months is common. 3M rates its HF20-S cartridge for one year or 9,000 gallons, and Ice-O-Matic says to replace its IOMQ cartridges every six months.
A filter does three jobs, and most cartridges do all three
- Sediment. A fine filter catches grit and rust. Manitowoc rates its Arctic Pure Plus cartridges at 0.5 micron.
- Carbon. It takes out chlorine taste and smell. Manitowoc states a 95% average chlorine reduction for Arctic Pure.
- Scale inhibitor. A slowly dissolving phosphate keeps the minerals in solution, so they pass through instead of sticking to the plate.
A scale inhibitor slows scale, but it does not remove the minerals
The inhibitor does not take the minerals out of the water. It keeps them dissolved, so less of them coat the plate. The machine still needs its clean and sanitize on the maker's schedule, every six months for most, and more often on hard water: Scotsman says four times a year where the water is highly mineralized.
Soft, cloudy or slow ice often starts with the water
Manitowoc's manuals list poor incoming water and poor filtering among the first causes of soft or cloudy ice, with a dirty machine and a dirty screen at the water inlet. Their fix includes having a qualified company test the water and recommend a filter.
A clogged cartridge also cuts the water flow. That can slow the machine or stop it filling. Commercial ice machine repair has the other checks.
Change the cartridge on its date or its gallons, whichever comes first
Each cartridge is rated for a number of months and a number of gallons. A busy machine reaches the gallons first; a quiet one reaches the date first.
Cartridge | Rated for | Notes |
|---|---|---|
3M HF20-S (for the ICE120-S system) | 1 year or 9,000 gallons | Whichever comes first |
Manitowoc Arctic Pure Plus AR-10000-P | 15,000 gallons | 0.5 micron, with a scale inhibitor |
Ice-O-Matic IOMQ | Every 6 months | For the IFQ systems |
Write the install date on the cartridge. It is the only way the next person knows how old it is.
Choose the filter by the machine's maker and its ice output
- Start with the maker's own line. Manitowoc sells Arctic Pure, Scotsman sells AquaPatrol, and Ice-O-Matic sells the IFQ systems. Each fits its own machines.
- Size it to the machine. Filters are sized by how much ice the machine makes. Scotsman's AP3-P, for example, is for cubers over 1,300 lb.
- Test hard water first. If scale returns fast, a water test tells you what the filter has to handle.
- Ask before you fit reverse osmosis. Ice-O-Matic warns that RO water without a neutral pH can void the warranty.
Then follow the label on the filter head for how to change the cartridge and flush it.
The filter change is a PM row of its own
Task | How often | Who | Notes |
|---|---|---|---|
Clean and sanitize the water system | Every 6 months for most makers (Hoshizaki KM: at least yearly), or the manual's interval. More often with hard water | Trained staff or a service company | Use the cleaner and sanitizer the manual names. Never mix them |
Wash the bin | At each clean | Trained staff | With the solution the manual gives |
Throw away the first batches after a clean | At each clean | Trained staff | Ice-O-Matic says the first two batches after cleaning, and again after sanitizing |
Change the water filter cartridge | On its date or its gallons, whichever comes first | Trained staff | Write the date on the cartridge |
Check and clean the air-cooled condenser | At each clean, or as the manual says (some makers say monthly) | Trained staff, power off | Vacuum or soft brush |
Check the condenser air filter, where fitted | Twice a month (Hoshizaki KM-255BAH) | Anyone | Rinse or replace as the manual says |
SiteWise keeps the ice machine's PM on schedule and the history in one place
A cartridge looks the same on its last day as on its first, so the change gets skipped.
And the filter is one job on one machine. The same machine needs a clean, a sanitize, the bin washed and the condenser kept clear, each on its own interval. A kitchen or a site often has 10 to 15 machines like it, each with a list of its own. A paper checklist on the wall cannot keep that many dates, and it cannot tell anyone when one is missed.
SiteWise keeps all of it on your phone, in a free app. Yes, really free: the free plan has unlimited work orders (100 open at a time), 20 locations and 250 assets, far more than 15 machines.
Or open renergytech.com/download/sitewise on your phone.
SiteWise is a CMMS (a computerized maintenance management system): software that holds the assets, schedules the PMs, issues the work orders and keeps the history.
- The PM. Set the clean every 6 months, or the interval your manual gives. SiteWise creates the work order a set number of days before it is due, or schedules the next one from when the last was done.
- The procedure. Attach the maker's steps, with photos, to the PM, so whoever does the clean uses the right cleaner at the right amount.
- The parts. Keep cleaner, sanitizer and filter cartridges as parts with a minimum per storeroom. SiteWise reserves the parts for a planned PM 30 days ahead.
- On the phone. Technicians create, update and close work orders and PMs offline, on every plan, add photos and videos up to 30 seconds, and scan the machine's QR code to open its history.
Keep cartridges as parts in SiteWise with a minimum per storeroom; the consumption ledger projects what your planned PMs will use.
Download the PM schedule above as a spreadsheet: ice machine PM schedule (CSV). The plans are on the SiteWise page.