Unicel C-8399 | 100 sq ft Caldera Spa Filter
TheĀ Unicel C-8399Ā is aĀ large-capacityĀ spa filter cartridge deliveringĀ 100 square feetĀ of filtration acrossĀ 259 pleatsĀ ofĀ ReemayĀ® 2033 polyester media, capturing debris down to an average ofĀ 20 microns. Built toĀ meet or exceed OEM specifications, it's the replacement cartridge forĀ CalderaĀ® Spas, taking the place of Caldera partĀ 1039607.
Filtration is the quiet backbone of clean spa water. Every soak leaves behindĀ body oils, lotions, hair, and fine debris, and the cartridge is what removes all of it before it clouds the water, feeds bacteria, or coats your plumbing. When a filter is worn or clogged, the effects spread everywhere: dull water, higher chemical use, softer jets, and aĀ pump and heater strainingĀ against restricted flow.
This is a serious cartridge āĀ 16-1/2 inches tallĀ with a fullĀ 100 square feetĀ of filtering surface packed intoĀ 259 pleats, one of the highest pleat counts Unicel makes. That capacity is exactly what a large, jet-heavy Caldera spa demands. AĀ semi-circular handleĀ molded into the top makes lifting it out effortless, while theĀ 3-5/8 inch open bottom with a lip sealĀ seats into the housing for a positive, leak-free connection. Add Reemay's trilobal fibers andĀ chemical-resistant end caps, and you get a cartridge built to perform through cleaning after cleaning. Made in the USA.
UNICELĀ®
UNICELĀ® Brand FAQs
Who makes Unicel filters?
Unicel filters are made byMeissner Mfg. Co., Inc., a family business that began as a small contract sewing operation in thelate 1950sand moved into pool filtration through the 1970s. By the end of that decade the company was producing cartridge filters for the industry'soriginal equipment manufacturers, and in1985it introduced the Unicel brand as aftermarket replacements. It's still owned and operated by the Meissner family today.
Are Unicel filters as good as the original manufacturer's filter?
Unicel builds its cartridges tomeet or exceed original equipment specificationsā and that's a meaningful distinction here, because the company produced cartridges for the industry's OEMs before it ever launched its own brand. Unicel cartridges usedurable, chemical-resistant end capswith an exact fit,high-capacity media,uniform pleatsfor optimal flow, and asolid corethat resists collapsing under pressure.
Where are Unicel filters made?
Unicel filters are manufactured inCalifornia, with components sourcedexclusively in the United States. The line comprisesnearly 500 products, covering replacement cartridges, D.E. grids, filter discs, and related parts.
How do I find the right Unicel filter for my spa?
Unicel cartridges areinterchangeable with all major filter brands, and each one cross-references to a list of original equipment part numbers. The most reliable method is topull your current cartridge and read the part number printed on it, then match it to the Unicel cross-reference. If the number has worn off,measure your old cartridgeā diameter, length, and the size and style of the openings at each end ā and match those instead. Also confirmhow many cartridgesyour spa uses.
How long does a Unicel filter last?
Cartridge life depends on how heavily the spa is used, yourwater chemistry, and how consistently you clean the filter. Many Unicel cartridges useReemayĀ® polyester media, whosetrilobal fibersprovide considerably more surface area than standard rounded fibers ā which increases dirt-holding capacity and extends the time between cleanings. With regular rinsing and periodic deep cleaning, a well-maintained cartridge commonly serves a year or more.
When should I replace my filter instead of cleaning it?
Replace the cartridge when thecycle between cleanings becomes noticeably shorter, when you seelow water flowor high differential pressure, when the media has atear, or if thecenter core collapses. Pleats that stay permanently flattened or discolored after a proper cleaning are another sign the cartridge has reached the end of its service life.
About UNICELĀ®
UnicelĀ is the nation's leading manufacturer of replacement filter cartridges for pools and spas ā and the story behind it is a genuinely American one. In the late 1950s,Ā Richard T. MeissnerĀ started a small part-time contract sewing operation. Through the 1970s, Meissner Mfg. Co., Inc. moved into swimming pool filter bags, then D.E. grid element covering, and by the end of that decade the company was producingĀ cartridge filters for the industry's original equipment manufacturers.
That's the detail that matters most: Unicel wasĀ building the filters that went into new spas long before it sold a replacement. InĀ 1985, the company introduced the UNICEL brand so dealers and technicians could source elements built to O.E.M. specifications from a single place ā even for equipment brands they didn't carry. Today the line spansĀ nearly 500 products, all manufactured inĀ California with components sourced exclusively in the USA.
By staying focused on one thing ā filtration ā Unicel has built deep expertise in a critical corner of the industry, from media development to cartridge design. Every cartridge is built withĀ chemical-resistant end capsĀ for an exact fit,Ā high-capacity filter media,Ā uniform pleatsĀ for optimal flow, and aĀ solid coreĀ that holds its shape under pressure. Meissner Mfg. Co., Inc. remainsĀ owned and operated by the Meissner family, still recognized for quality and service. American-made products, world-class service.




