The Scotsman AP3-P is an Aqua Patrol Plus water filter for Scotsman ice machines, built as a triple system for cubers over 1,300 lb. It inhibits scale and filters the water supplying the ice machine for commercial operators and facility teams running high-capacity Scotsman cubers.
This guide covers Scotsman AP3-P system installation for a first-time setup, which takes about 15–30 minutes. On-time replacement matters because an expired cartridge stops filtering and lowers water quality, and our APRC1-P filter replacement guide covers that procedure.
Safety & Preparation
Start by confirming the system fits the ice machine. The AP3-P is the triple system for cubers over 1,300 lb, with a maximum flow of 6.3 gpm. It uses three APRC1-P cartridges. SSM Plus cartridges are a separate line under different part numbers.
⚠️ Supply & Operating Limits
Choose the Mounting Location
The unit measures 21" W x 5.5" D x 19.26" H, and its shipping weight is about 16 lb. Choose an accessible wall or panel near the ice machine with room for those dimensions and for cartridge service.
AP3-P width, depth, and height, with the inlet and outlet positions
Check that the supply line and the ice machine line can both reach the unit from the chosen spot. The connection order is covered in Step-by-Step Installation.
🚰 Inlet
3/4" MNPT. Connects to the incoming water supply line.
🧊 Outlet
3/4" FNPT. Connects to the ice machine's water inlet.
Have Everything Ready
Unpack the system and read the included instructions before starting.
🧰 Materials
Included with the system:
You will also need:
⚠️ Safety Precautions
Step-by-Step Installation
Common Installation Mistakes
Review these points before and during a Scotsman AP3-P system installation. Red cards show what to never do, and amber cards show mistakes you can prevent or fix.
Never start the system outside the pressure and temperature ranges in Safety & Preparation.
Never use SSM Plus cartridges or leave a position empty. Fill all three positions with the Aqua Patrol Plus APRC1-P.
Keep the head vertical and leave clearance for cartridge service. Check the position before tightening the mount.
Check the inlet and outlet markings, and keep the outlet off the ice machine until the flush is done. To correct either one, shut off the water first.
A loose cartridge can leak at the manifold. Shut off the water and reseat it, following the included instructions.
Open the supply valve fully, since a partly open valve reduces flow. Check each joint and the manifold for leaks before the machine goes into service.
If a cartridge will not seat or remove easily, stop and ask a licensed plumber or authorized Scotsman service technician for help.
What to Expect After Installation
The flush in step 5 of Step-by-Step Installation is a key part of any Scotsman Aqua Patrol Plus system installation. Run water through the system for several minutes before connecting the outlet to the ice machine. This clears trapped air and loose carbon particles, so seeing both during the flush is normal.
Once the outlet is connected and the supply is fully open, compare the system with the two columns below:
✅ Normal After Connecting
🔎 Worth a Second Look
🟢 Ready for use: the system holds with no leaks, flow is steady, and the water is clear.
If anything in the right-hand column appears, recheck the cartridge seating and confirm the supply valve is fully open. If the problem continues, have a licensed plumber or authorized Scotsman service technician inspect the system.
Record the install date to start the schedule in When to Replace Your Filter Cartridge.
Official Product Resources
Use the Scotsman spec sheet to check AP3-P dimensions, flow, operating limits, and NSF/ANSI 42 and 53 details.
When to Replace Your Filter Cartridge
Replace the cartridges typically every 6 months, depending on usage and water quality, or sooner if flow drops noticeably. Each replacement covers all three cartridges. These three checks help set the schedule:
The usual schedule, adjusted for usage and water quality.
A noticeable drop means it's time to replace them sooner.
Higher ice production or poorer incoming water can shorten the schedule.
To stay on schedule without tracking dates, the filter subscription is a set-it-and-forget-it option. It ships the APRC1-P 1-pack every 6 months and saves 10%. The quantity is not set automatically, so select 3 when you subscribe to cover all three cartridges.
The replacement cartridge is the genuine Scotsman APRC1-P, and each AP3-P replacement takes three. The APRC6-P 6-pack is the stock-up option because it covers two full replacements. For the procedure, follow the APRC1-P filter replacement guide.
🔎 More from Scotsman: Browse the full Scotsman collection, including ice machines, water filter systems, and replacement cartridges.
How to Maximize the Lifespan of Your Filter
A few simple practices keep the AP3-P clean, accessible, and operating properly:
- Log each date — record the installation and every replacement against the schedule in When to Replace Your Filter Cartridge.
- Inspect the system periodically — look for leaks or reduced flow.
- Keep the unit accessible — leave room around it for inspection and cartridge service.
- Stay within the rated limits — keep operating conditions inside the ranges in Safety & Preparation.
- Use genuine cartridges — install only genuine Scotsman replacement cartridges.
- Keep all three positions current — filtration and polyphosphate scale control both depend on a current cartridge.
Troubleshooting & FAQ
Is the AP3-P right for my ice machine?
The AP3-P is the triple Aqua Patrol Plus system for cubers over 1,300 lb, with a maximum flow of 6.3 gpm. The full fit check is in Safety & Preparation.
How many cartridges does the AP3-P use?
The AP3-P uses three cartridges. Pack options are in When to Replace Your Filter Cartridge.
Which way should the filter head be mounted?
Mount it vertically with the cartridges hanging down. The mounting step is in Step-by-Step Installation.
How long does installation take?
Allow about 15–30 minutes for a first-time installation.
Why flush before connecting the ice machine?
The flush clears trapped air and loose carbon particles and fills the system with water before the outlet is connected to the ice machine. The flush time is in What to Expect After Installation.
Why does the water show air or carbon particles at first?
Air trapped in the new system and loose carbon particles from the new cartridges are normal during the flush and should clear as the water runs. If they continue, follow the checks in What to Expect After Installation.
What should I check if a connection or the manifold leaks?
Shut off the water supply, then check that the connections are tight and the inlet and outlet are not reversed. For a leak at the manifold, reseat the cartridges before opening the supply again. More causes are in Common Installation Mistakes.
Why is flow low after installation?
A partly open supply valve or a cartridge that is not fully seated can reduce flow. Open the valve fully and recheck all three cartridges. If flow stays low, see What to Expect After Installation.
Why does Aqua Patrol Plus leave chlorine in the water?
Scotsman designed Aqua Patrol Plus to leave chlorine in the water to keep the ice machine cleaner longer.
How often do the cartridges need replacing, and which cartridge fits?
Replace all three cartridges typically every 6 months, or sooner if flow drops noticeably, depending on usage and water quality. The AP3-P takes the Scotsman APRC1-P Aqua Patrol Plus replacement cartridge. Schedule details are in When to Replace Your Filter Cartridge.
When should a plumber or authorized Scotsman technician take over?
Bring one in if leaks, weak flow, air, or particles continue after you recheck the cartridges and supply valve, or if a cartridge will not seat or remove easily.
Product & Replacement Options
These related products cover ongoing cartridge supply and sites comparing system sizes. You can also browse the full Scotsman collection:
A single Aqua Patrol Plus replacement cartridge from an open-box listing. The cartridge is unused, but the packaging may show wear, and open-box orders are not returnable.
View Product →Six cartridges from an open-box listing, enough for two full AP3-P replacements. The same open-box condition and return terms apply.
View Product →The two-cartridge Aqua Patrol Plus system for smaller machines. It suits cubers up to 650 lb and flakers, nuggets, and nugget dispensers up to 1,200 lb, with a maximum flow of 4.2 gpm.
View Product →🧊 Shop Scotsman Ice Machines & Water Filters
Never Run Out of Replacement Cartridges
Auto-delivery is the easy way to keep APRC1-P cartridges on hand, with shipments every 6 months and 10% savings.
Conclusion
The AP3-P installs in seven steps, all covered in Step-by-Step Installation. Mount the unit vertically, install all three cartridges, and connect the inlet. Flush the system before connecting the outlet to the ice machine, then open the supply fully and check for leaks.
After startup, log the install date and keep to the schedule in When to Replace Your Filter Cartridge. Our APRC1-P filter replacement guide covers the procedure when the cartridges are due.