Jacuzzi Earthworks EW DE Filter: Grids by Model, the Dial Valve and the Tank O-Ring — and Why CFR and Laser Parts Won't Fit

The Jacuzzi Earthworks is an odd filter to service for the first time. Where every other DE filter on the pad has a clamp band in the middle and a multiport or push-pull valve plumbed to the side, the Earthworks has a lock ring on top, a stack of flat vertical grids in three different widths inside, and its backwash valve built into the bottom of the tank as a rotating "dial." Parts listings make it worse: Jacuzzi's CFR (cartridge), Laser (sand) and Avalanche/Landslide (DE) lines are all filed under the same brand, and the numbers look alike.

This guide covers the EW75, EW100, EW125 and EW150 — the four sizes that share one tank design and one dial valve — with a section at the end on the other Jacuzzi filters so you stop ordering the wrong thing. Jacuzzi's pool equipment line has since been sold under the Carvin name, which is why a search for these numbers turns up both brands; the parts are the same.

Reading the symptoms

The Earthworks fails the same three ways as any DE filter, and the pressure gauge plus the pool tell you which.

Torn fabric is the most common cause of DE in the pool by a wide margin, and it does not take much: a pinhole or a run of unravelled stitching is enough. The second most common is the cross-shaped manifold cracking around the air-bleed boss, usually from a return-side valve being closed with the pump running. On the Earthworks the third suspect is specific to this design — the dial valve seals — because the valve sits in the tank bottom under the full weight of the grid stack and its foam sealing washer takes a set.

Prep and safety

Pump off at the breaker. Open the air bleed on top until the gauge reads zero. On a pad below water level, close the suction and return isolation valves before touching the lock ring. Have a hose, a soft brush and a bucket ready: the grids will come out coated in wet DE, and the inside of the tank will need a rinse before you can see anything.

The lock ring on top is plastic. If it is stiff, tap it round with a soft mallet rather than levering on it; a cracked lock-ring nut is a leak you will chase for a week. The replacement is the 42293506R cover lok-ring nut, and it pairs with the 4669-04 retainer ring underneath that actually holds the tank top down.

Which grids you have: mixed widths, one height per model

Lift the tank top and the grid assembly comes into view: flat rectangular grids standing vertically around a central manifold, in two or three different widths so they pack the round tank efficiently. That mixed-width layout is the thing that trips people up when ordering. The height is fixed by the model; the widths are mixed within the set.

Suppliers disagree in print about how many of each width the tank holds, so do not order from a table — including this one. Count what comes out of your tank by width and replace one for one. The good news is that within a model every grid of a given width is identical, so a set with one torn 7-inch grid needs one 7-inch grid, not a full set.

Inspect every grid, not just the one that looks bad. Hold each up to the light and look for pinholes, stitching that has opened along the seam, and cracks in the plastic collar where the grid plugs into the manifold — a cracked collar lets DE straight into the clean side even with perfect fabric, and it means the grid is scrap. Fabric that is stiff, brown and does not rinse clean has oils and calcium in it; a soak in a DE filter cleaner will recover it once or twice, and after that it is a replacement.

The older Earthworks EW36 through EW72 used a different internal assembly on the same tank and valve. For those the grid pack is sold as a manifold-and-grid unit — 4638-61 for the EW48, 42-3597-20-K for the EW60 — rather than as individual grids.

The manifold, the air bleed and the tank seals

The grids plug into the 4638-02A manifold. Look at it with the grids out: cracks radiate from the sockets and from the air-bleed boss in the centre, and a hairline is enough to pass DE. Manifolds crack from water hammer and from being reassembled with a grid collar sitting on the rim of its socket instead of in it, so when you refit the grids, make sure every collar clicks fully home before the retainer goes on.

The air bleed is a two-piece affair on this filter: the 4669-08 air bleed assembly is the quarter-inch PVC line and tee that carries air from the manifold up to the top, and the 39254701R air bleeder valve with o-ring is the valve you open to purge it. A drip from the bleeder after it is closed is the o-ring; a bleeder that will not purge air is a blocked line, and a filter that cannot purge air runs a pocket of air under the lid that lets DE through when the pump stops and starts.

The tank o-ring sits between the top and bottom halves under the retainer ring. It is a 20-inch ring — the EW tank top is the same moulding as the Tri-Clops cartridge filter's — and our 47056999R cross-references to Jacuzzi's 4610-60. Clean the groove, lubricate with a pool-grade silicone lubricant, and never reuse an o-ring that has flattened or shows nicks from the last time the top came off. If the tank top itself is cracked at the lock-ring threads or the gauge boss, the 4669-10A replaces the EW100 top (also the TC-450), and 4669-07 is the tank bottom.

The dial valve

This is the part that makes the Earthworks the Earthworks. Instead of an external multiport, a rotating plate in the base of the tank directs flow to filter, backwash, rinse or waste according to where the handle points. The 4638-05 dial valve assembly is the whole rotating unit; around it are the parts that wear.

The valve seals in two places. The 4638-11 foam washer gasket — three inches across — seals the rotating plate against the tank base, and the 47021266R dial valve o-ring seals the shaft. The 4638-07 shaft spring is what keeps the plate loaded against the gasket; a spring that has lost its tension lets the plate lift under pressure and DE crosses to the pool side, which is exactly the "powder only after recharging" symptom in the table above. The 4638-08 handle and 4638-10 thumb screw are the parts that break in the hand, and the 4638-09 foam washer sits under the handle.

Two rules for this valve. First, never move the handle with the pump running — that is how the foam gasket gets torn, on this filter and every other. Second, when you have the grids out and the tank bottom is accessible, replace the foam washer gasket and o-ring as a matter of course. They cost almost nothing against the labour of opening the tank a second time, and a foam gasket that has been compressed for ten seasons does not spring back.

Reassembly and first run

Fit the grids to the manifold, checking each collar seats fully, and lower the assembly onto the dial valve so the manifold engages the valve outlet squarely. Clean and lubricate the tank o-ring, seat the top, fit the retainer ring, and run the lock-ring nut down by hand until it stops, then a quarter turn — no tools. Open the air bleed, start the pump, and close the bleed once it sprays solid water.

Add DE only with the handle in the filter position and the pump running, through the skimmer, slowly, at the rate the filter's label states for its square footage — a bag dumped in at once is the surest way to push powder past a good valve and straight to the pool. Note the clean pressure; that number is your baseline for the next backwash decision.

Which Jacuzzi filter you actually have

The Earthworks parts listing sits next to three other Jacuzzi filter families, and the numbers look similar enough that the wrong part gets ordered constantly.

CFR 25 / 50 / 75 / 100 / 150 — cartridge filters. No grids, no DE, no backwash valve. The tank opens at the top with the 42285007 lock ring and the 42-2852-05-R tank lid on the CFR 50 and CFR 100; the pleated cartridge sits over a "dirt catcher" cup — 4666-15 for the 50, 4666-15B for the 100, 4666-15E for the 150. The 4628-08 gauge lens, 4666-07 drain plug and 4638-30 locking tabs are the other parts that go. If a customer says "Jacuzzi filter, no valve, I take the element out and hose it," it is a CFR.

Laser 160L / 190L / 225L / 250L — sand filters. A round tank with a multiport valve on top, sand inside, and a lateral-and-standpipe assembly at the bottom. Parts are laterals (85531203R8 for the L190 and L225, 85531304R8 for the 250L, 42351700 for the Sandstorm and L250), standpipes (42377408K for the 250L, 42377101K for the L190, 4625-08A upper standpipe), the 4626-13 drain nozzle with its 14255202R retainer, the 4626-16 drain cap and the 47-0434-01 six-and-an-eighth-inch tank o-ring. Nothing from the Earthworks fits a Laser, and a Laser never puts DE in a pool because there is no DE in it — cloudy water from a Laser is broken laterals passing sand.

Avalanche AV40 / AV60 / AV80 and Landslide LS40 / LS55 / LS70 — DE filters, different grids. These are the later Jacuzzi DE designs, and they use their own grid sizes: 42356907R (8½ × 12) and 42357004R (7 × 12) for the AV40 and LS40, 42295105R (8½ × 24) for the AV-80 and LS-70. The 4638-28 manifold, 4638-26 wiper plate and 4638-23 upper support plate are Avalanche and Landslide parts, not Earthworks. Grids from these tanks are the wrong height for an EW, and the EW grids are the wrong height for them.

Model pages for each family carry the full list of parts that fit: Earthworks EW75, EW100, EW125, EW150; CFR 50, CFR 100, CFR 150; Laser 160L through 250L; Avalanche and Landslide. For the Hayward equivalent of this article, see which Hayward DE grid do I need.

Cross-reference table

Where Jacuzzi (and Carvin) published an alternate number for the same part, both are listed. Numbers without a second Jacuzzi reference are direct equivalents of the number shown.

Sourcing

POOLPOINT manufactures the Earthworks grids, manifold, retainer and lock rings, tank o-ring, air-bleed parts and dial valve components factory direct for US distributors, service companies and online sellers — along with the CFR, Laser and Avalanche/Landslide parts above. MOQ starts at 50 pieces per SKU, mixed cartons are accepted to reach it, and private label is available. A full grid set for an EW150 and a bag of dial-valve seals is a sensible truck stock item in any territory where these filters are still common. Request a quote for wholesale pricing.