Unicel C-7479 | 75 sq ft Caldera Spa Filter

By Unicel
SKU: C-7479
$76.99

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Check out the Filter Guide to see if this filter fits your hot tub model.

If you have questions, call us at (208) 973-1384 or send us an email to hello@leisuretimeinc.com

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Description

The Unicel C-7479 delivers 75 square feet of filtration across 216 pleats of Reemay® 2033 polyester media. Built to meet or exceed OEM specifications, it's the replacement cartridge for Caldera® Spas models using OEM part 033017.

Filtration is the quiet backbone of clean spa water. Every soak leaves behind 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 a pump and heater straining against restricted flow.

This is a substantial cartridge — 14-3/4 inches tall with 75 square feet of filtering surface — sized for the demands of a full-size Caldera spa. A semi-circular handle molded into the top makes lifting it out effortless, while the 2-inch male slip fitting on the bottom seats into the housing connection for a positive seal. The media is Reemay, whose trilobal fibers deliver roughly 45% more surface area than standard rounded filter fibers, so it captures more and releases dirt readily when rinsed. Made in the USA.

Pro Tip: Check the bottom fitting — it's the only thing separating this from the C-7375. Both cartridges are 75 sq ft with 216 pleats, both measure 7 by 14-3/4 inches, and both have a semi-circular handle on top. The difference is underneath: this C-7479 has a 2-inch male slip fitting, while the C-7375 has a 2-11/16 inch open bottom. Turn your old cartridge over before ordering — that one look settles it.

Brand

UNICEL®

Key Features
  • 75 sq ft of filtration — full OEM-spec filtration area across 216 pleats
  • Direct Caldera replacement — takes the place of OEM part 033017
  • 45% more surface area — Reemay trilobal fibers outperform standard rounded fibers
  • Semi-circular handle — makes removal and cleaning effortless
  • 2 in male slip bottom — seats positively into the housing connection
  • Made in the USA — built to meet or exceed OEM standards
How It Works

Water is drawn through the cartridge's pleated media as your spa circulates. Pleating creates the capacity: folding the fabric into 216 pleats packs 75 square feet of filtering surface into a cartridge 7 inches across and 14-3/4 inches tall. More surface means water passes through more slowly and thoroughly, capturing finer particles, and it means the filter holds far more debris before flow starts to drop off.

The media does the rest. Reemay fibers are trilobal — three-lobed in cross-section rather than round — which delivers roughly 45% more surface area than standard rounded filter fibers, giving more places for dirt to be captured and a smooth surface that releases it readily when rinsed. Just as important is the slip fitting: it seats the cartridge positively into the housing so water is forced through the media rather than slipping around a loose connection. A cartridge that isn't sealing properly filters far less than its rating suggests.

Pro Tip: A clean filter protects your equipment, not just your water. As the pleats load up with body oils, your pump has to work harder against the restriction, and reduced flow across the heater can trigger flow-related errors. Regular rinsing and periodic deep cleaning is the cheapest protection there is for the expensive parts of your spa.

Directions for Use

Installation

  1. Turn off power to the spa at the breaker before servicing the filter compartment.
  2. Open the filter lid and clear any debris from the compartment.
  3. Lift the old cartridge out by its handle, noting its orientation.
  4. Lower the new cartridge in with the slip fitting facing down, seating it firmly into the housing connection so it seals properly.
  5. If your spa uses more than one cartridge, replace them at the same time so they wear evenly and flow stays balanced.
  6. Close the lid, restore power, and run the circulation to confirm normal flow.

Routine Cleaning

  1. Every two to four weeks: lift the cartridge out by the handle and rinse gently with a garden hose, working between the pleats from top to bottom. A soft brush cleaning tool helps.
  2. Periodically: soak or treat the cartridge with a dedicated filter cleaner to dissolve the body oils and buildup a rinse can't remove, then rinse it off.
  3. Let it dry fully before returning it to service whenever possible.

When to Replace

  • The cycle between cleanings gets noticeably shorter
  • Low water flow or high differential pressure
  • The media has a tear
  • The center core collapses

Cartridge life depends on routine maintenance and your spa's water chemistry.

Pro Tip: Inspect the slip fitting each time you clean the filter. That plastic collar is what creates the seal between the cartridge and the housing, and a crack, burr, or distortion there will let unfiltered water bypass the media entirely — even when the pleats look spotless. It's a five-second check while the cartridge is already out, and it explains cloudy water that no amount of chemistry seems to fix.

Specifications
  • Brand: Unicel (Meissner Mfg. Co., Inc.)
  • Part Number: C-7479
  • Series: Unicel 7000 Series
  • Product Type: Replacement spa filter cartridge
  • Filtration Area: 75 sq ft
  • Pleat Count: 216
  • Media: Reemay 2033 spunbonded trilobal polyester, 3 oz basis weight
  • Outer Diameter: 7 in
  • Length: 14-3/4 in
  • Top: Semi-circular handle
  • Bottom: 2 in male slip fitting
  • End Caps: Durable plastic, chemical-resistant, exact OEM fit
  • Fits: Caldera Spas models using the 033017 cartridge
  • Replaces OEM: Caldera Spas 033017
  • Cross-References: Pleatco PCD75, Filbur FC-3085, RJ Filtration AK-6050
  • Alternate: Unicel notes the C-7375 can also be used as a replacement in this application
  • Not the Same As: The C-7375 in general fitment — identical size and pleat count, but a 2-11/16 in open bottom instead of a 2 in male slip fitting
  • Cleaning: Rinse gently with a garden hose every two to four weeks; deep clean periodically with filter cleaner. Do not pressure wash.
  • Origin: Made in the USA
  • Shipping: Standard ground; not classified as a hazardous material

  • Outer Diameter: 7"
  • Length: 14-3/4"
  • Top End Cap: semi-circular handle
  • Bottom End Cap: 2" male slip fitting
  • Pleat Count: 216
  • Media: 3 oz.
  • Filtration Square Footage: 75 sq. ft
Compatibility

The C-7479 is built for Caldera® Spas models using this cartridge. It serves as a direct replacement for:

  • Caldera Spas: 033017

It's also cross-referenced as Pleatco PCD75, Filbur FC-3085, and RJ Filtration AK-6050.

Unicel notes that the C-7375 can also be used as a replacement in this application — useful to know if you find that cartridge more readily available. The two share the same 75 sq ft rating, 216 pleats, and 7 by 14-3/4 inch body, differing only in the bottom end cap.

Before ordering, verify the 2-inch male slip fitting on the bottom, the semi-circular handle on top, and the 7 inch diameter by 14-3/4 inch length, since Caldera has used several cartridge designs across its model years. Also confirm how many cartridges your spa takes. The surest method is to pull your current cartridge and read the part number printed on it. For upkeep, pair it with a dedicated filter cleaner for periodic deep cleaning.

Most products purchased from our online shop within the last 30 days are eligible for return. Please review our return policy to see the list of items that cannot be returned.

Some major items that are non-returnable:

  • Gift cards
  • Electronics
  • Pumps / Motors
  • Hot Tubs
  • Closeouts
  • Fireplaces
  • Electric Fireplaces
  • Massage Chairs
  • See return policy below for full list of non-returnables.

UNICEL® 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 specifications— 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 cartridge— diameter, length, and the size and style of the openings at each end — 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 useReemay® polyester media, whosetrilobal fibersprovide considerably more surface area than standard rounded fibers — 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 UNICEL®

Unicel is the nation's leading manufacturer of replacement filter cartridges for pools and spas — and the story behind it is a genuinely American one. In the late 1950s, Richard T. Meissner 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 producing cartridge filters for the industry's original equipment manufacturers.

That's the detail that matters most: Unicel was building the filters that went into new spas long before it sold a replacement. In 1985, the company introduced the UNICEL brand so dealers and technicians could source elements built to O.E.M. specifications from a single place — even for equipment brands they didn't carry. Today the line spans nearly 500 products, all manufactured in California with components sourced exclusively in the USA.

By staying focused on one thing — filtration — Unicel has built deep expertise in a critical corner of the industry, from media development to cartridge design. Every cartridge is built with chemical-resistant end caps for an exact fit, high-capacity filter media, uniform pleats for optimal flow, and a solid core that holds its shape under pressure. Meissner Mfg. Co., Inc. remains owned and operated by the Meissner family, still recognized for quality and service. American-made products, world-class service.