Unicel Replacement Filter Cartridge 20 Sf | 4CH-925
Unicel
SKU: 4CH-925
Unicel 4CH-925 Replacement Spa Filter Cartridge – 20 Sq Ft (4-5/8" OD x 7-1/4" Length, 1-1/2" SAE Thread)
The Unicel 4CH-925 is a top-load spa filter cartridge designed for select hot tubs and spa filter canisters that use a 1-1/2" SAE threaded (screw-in) bottom connection. It uses durable pleated media to capture fine debris for clearer water and more consistent flow when rinsed and cleaned on a regular schedule.
Key Features
- 20 sq ft filtration area for effective spa water polishing
- Bottom: 1-1/2" SAE screw-in thread for a secure fit in compatible housings
- Top: handle-style end cap for easy removal
- Replaces worn or damaged cartridges to help restore circulation and water clarity
- Built for repeated rinse and deep-clean cycles
Specifications
- Part Number: 4CH-925
- Filtration Area: 20 sq ft
- Outside Diameter: 4-5/8" (4.625")
- Length: 7-1/4" (7.25")
- Top End Cap: Handle (closed)
- Bottom End Cap: 1-1/2" SAE thread (injection molded)
- Pleat Count: 190
- Media: 3 oz pleated media
Replaces / Cross References
- Pleatco: PSANT20P3
- Filbur: FC-0126
- Darlly: 42524
- Baleen: AK-90083
Compatibility Notes
- Designed for spa filter canisters that require a 1-1/2" SAE screw-in cartridge with a 4-5/8" diameter body.
- Often used in select spa brands such as Strong, Softsider, and Futura (verify by measurements and thread style).
- Always confirm fit by matching the OD, length, and bottom thread type to your existing cartridge.
When to Replace
- Pleats are torn, frayed, flattened, or separating from the end caps
- Flow is weak or the system struggles to maintain circulation even after cleaning
- Water stays cloudy despite balanced chemistry and normal sanitizer levels
- End caps or the threaded connection are cracked/warped and won’t seal properly
Related Products
- Spa Cartridge Filter Cleaner
- Cartridge Cleaning Wand
- Spa Water Test Strips
- Spa Fill / Hose Pre-Filters
- Silicone O-Ring Lubricant (Pool/Spa)
Maintenance Tips
- Rinse the cartridge frequently (often weekly with regular spa use) to prevent restriction and keep flow strong.
- Deep clean every 3–6 weeks with a cartridge cleaner to remove oils; rinse thoroughly before reinstalling.
- If scale is present, degrease first, then treat for scale (never reverse the order), and rinse completely.
- Rotating between two cartridges (one in use, one drying after cleaning) can extend overall filter life and improve filtration.
Questions about returns? View our return policy.
Hours Of Operation:
Monday - Friday: 7:00 am to 5:00 pm Phoenix Time
Saturday: 8:00 am to 2:00 pm
Sunday: Closed
- We do not ship on Saturday or Sunday.
- Orders totaling more than $300 will require signature confirmation upon delivery.
- We process and prepare orders for shipment within 1 business day. Please note that many other pool supply retailers require 3–5 days of handling time before shipping.
- Orders placed after 1:00 pm Phoenix Time may not be eligible for same-day shipment.
- Expedited shipping options are available at checkout.
Return Policy:
- Products that are received damaged will receive a refund in store credit.
- Most products are eligible for return within 30 days of receipt, except where noted below.
- To initiate a return, please complete an RMA form prior to sending your item back.
- Original shipping costs are non-refundable and will be deducted from the return credit.
- Items returned missing accessories or original packaging, or that are not in the same condition as received, may be subject to a restocking fee of up to 100% depending on the condition of the item upon return.
- Some returns will be charged an automatic 15% restocking fee.
- We are unable to issue refunds for items that have been damaged or rendered inoperable due to installer error.
- Please complete the return form to receive your RMA number and return shipping label.
- Chemical products are not eligible for return under any circumstances.
- The Pentair Colorsync 618031 is not eligible for return.
- Pool cleaners are not eligible for return.
- Opened seals and o-rings are not eligible for return.
- Capacitors are not eligible for return.
- Plastic popup tools are not eligible for return.
- Automation components and circuit boards are not eligible for return.
- If a light is returned due to a reported malfunction and is found to be fully operational upon testing, return shipping costs and a restocking fee will be deducted from the refund.
- Orders refused at the time of delivery will be subject to the original shipping costs being deducted from the refund.
Related Products
