Hayward PerFlex Extended-Cycle D.E. Inground Pool Filter 7 lb

The Hayward Perflex W3EC75A is a 40 sq ft extended-cycle D.E. pool filter for in-ground pools. Patented Flex-Tube design cleans without backwashing. 7 lbs D.E. capacity, 80 GPM max flow, 2-micron filtration. Self-venting, integral check valve, easy-access clamp assembly. Direct replacement for EC75A. 1 year warranty. Hayward PerFlex W3EC75A 40 Sq Ft Extended-Cycle D.E. Filter: Maximum In-Ground PerFlex Capacity The W3EC75A is the larger of the two in-ground PerFlex models, stepping up from the W3EC65A (27 sq ft, 67 GPM) with a 40 sq ft filter area, a 7 lb D.E. charge, and an 80 GPM flow ceiling. It is the right choice when your pump output approaches or exceeds 67 GPM, when you want the longer bump cycles and lower operating pressure that additional filter area provides, or when replacing an existing EC75A installation. Like all PerFlex models, the W3EC75A uses patented Flex-Tubes that clean by bumping rather than backwashing. Spent D.E. is redistributed and reused rather than discharged, so no backwash valve, drain line, or grid acid washing is needed. A single 7 lb charge typically lasts several months before a full D.E. recharge is warranted. How the PerFlex Bump-to-Clean Cycle Works When operating pressure rises 10 to 12 PSI above the clean baseline: stop the pump, push the bump handle down slowly then up briskly, repeat 8 times. The Flex-Tubes compress and release, shedding the spent D.E. cake. Dirty and clean D.E. remix and recoat the tube surfaces. Restart the pump. Pressure typically returns near baseline and the existing charge continues filtering. This cycle repeats many times before a full sump drain and D.E. recharge is needed. Hayward PerFlex W3EC75A D.E. Filter Specifications SKU / Model W3EC75A Filter Type Extended-cycle D.E. (Flex-Tube) Filter Area 40 sq ft D.E. Capacity 7 lbs pool-grade D.E. powder Max Flow Rate 80 GPM Filtration Range 2 microns Backwash Valve Required No Cleaning Method Bump handle; no backwashing Port Size 1.5" NPT inlet and outlet Internal Element Patented Flex-Tube elements Check Valve Integral; prevents backflow when pump is off Air Relief Self-venting; automatically expels air Tank Material Heavy-duty glass-filled PPL; corrosion-free Application In-ground pools Replaces EC75A (direct replacement) Warranty 1 year Hayward PerFlex D.E. Filter Lineup All PerFlex models use the same Flex-Tube bump-to-clean design with no backwash valve required. In-Ground PerFlex D.E. Filters Product Filter Area D.E. Charge Flow Rate Hayward PerFlex 27 Sq Ft D.E. Filter 27 sq ft 6 lbs 67 GPM Hayward PerFlex 40 Sq Ft D.E. Filter (this model) 40 sq ft 7 lbs 80 GPM Above-Ground PerFlex D.E. Filters Product Filter Area D.E. Charge Flow Rate Pump Hayward Perflex D.E. Filter with Clamp 4 lb 20 sq ft 4 lbs 40 GPM Filter only Hayward Perflex D.E. Filter System 4 lb 1 HP Pump 20 sq ft 4 lbs 40 GPM 1 HP PowerFlo Matrix Hayward Perflex D.E. Filter with Clamp 5 lb 25 sq ft 5 lbs 50 GPM Filter only Hayward Perflex D.E. Filter System 5 lb 1.5 HP Pump 25 sq ft 5 lbs 50 GPM 1.5 HP PowerFlo Matrix Hayward PerFlex W3EC75A D.E. Pool Filter Frequently Asked Questions What is the difference between the W3EC75A and W3EC65A? The W3EC75A has a larger 40 sq ft filter area (vs. 27 sq ft), a 7 lb D.E. charge (vs. 6 lbs), and an 80 GPM flow ceiling (vs. 67 GPM). The larger filter area means longer intervals between bump cycles, lower sustained operating pressure, and more headroom for high-output pumps. If your pump output approaches or exceeds 67 GPM, the W3EC75A is the correct choice. How often does the D.E. charge need replacing? Significantly less often than in a conventional D.E. filter. Because the bump mechanism reuses D.E. rather than flushing it, a single 7 lb charge typically lasts several months under normal conditions. Most owners replace the full charge one to three times per season rather than after every cleaning cycle. What D.E. powder is compatible? Standard pool-grade diatomaceous earth. Do not use food-grade, pest-control, or industrial D.E. Perlite is also compatible as a silica-free alternative to pool-grade D.E. D.E. is returning to the pool through the return fittings. What should I do? This indicates a Flex-Tube element has a breach allowing D.E. to bypass the filter media. Stop the pump, drain the tank, remove the tube assembly, and inspect each element. Replace any tube with a visible hole or seam failure before recharging and restarting. Is this a direct replacement for the EC75A? Yes. The W3EC75A is the direct replacement for the EC75A with the same specifications, Flex-Tube element design, and tank footprint. Hayward PerFlex W3EC75A D.E. Pool Filter Manual and Warranty Info Hayward PerFlex W3EC75A - Owner's Manual (PDF) Hayward PerFlex W3EC75A - Parts Diagram and Replacement Part Numbers (PDF)