Skip to content

Hayward Perflex D.E. Above Ground Pool Filter with Clamp 4 lb

✓ Hayward Authorized Dealer
✓ Includes Manufacturer Warranty
✓ Installation Available Upon Request
✓ 30-Day Return Policy Guarantee

$569.00

Notify me when back in stock

The Hayward Perflex W3EC40AC is a 20 sq ft extended-cycle D.E. pool filter for above-ground pools. Patented Flex-Tube design cleans without backwashing. 4 lbs D.E. capacity, 40 GPM max flow, 2-micron filtration. Clamp assembly included. 1 year warranty.

Hayward Perflex W3EC40AC 20 Sq Ft Above-Ground D.E. Filter: Extended-Cycle Filtration Without Backwashing

The Perflex W3EC40AC is the entry-level above-ground PerFlex model, providing 2-micron D.E. filtration for above-ground pools without a backwash valve, drain line, or grid teardown. The patented Flex-Tube design cleans through a bump handle instead of backwashing — stop the pump, stroke the handle eight times, and restart. The existing 4 lb D.E. charge redistributes and recoats the Flex-Tubes, restoring filtration without discharging media or wasting treated pool water.

The clamp assembly allows quick access to the filter interior without tools. If you also need a pump, the W3EC40C92S bundles this same filter with a 1 HP PowerFlo Matrix pump. For more filter area at the same above-ground scale, the W3EC50AC (25 sq ft, 50 GPM) is the step up.

Hayward W3EC40AC Perflex D.E. Filter Key Features

  • Patented Flex-Tube design - Bump-to-clean mechanism reuses D.E. powder rather than flushing it, extending filter cycles and eliminating the need for a backwash valve or drain line.
  • 2-micron filtration - Removes particles significantly finer than sand or cartridge filters, capturing dust, pollen, and algae spores on the first pass.
  • Clamp assembly - Tool-free access to the filter interior for inspection, D.E. recharge, and Flex-Tube servicing.
  • Self-venting design - Automatically expels air from the system through the filtered water returning to the pool.
  • Integral check valve - Prevents system backflow whenever the pump is off, protecting D.E. coating on the Flex-Tubes.
  • Combination pressure gauge and service port - Easy to read, easy to remove when the filter needs servicing.
  • Heavy-duty glass-filled PPL tank - Corrosion-free construction for outdoor above-ground pool installations.

Hayward W3EC40AC Perflex D.E. Filter Specifications

SKU / Model
W3EC40AC
Filter Type
Extended-cycle D.E. (Flex-Tube)
Filter Area
20 sq ft
D.E. Capacity
4 lbs pool-grade D.E. powder
Max Flow Rate
40 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
Above-ground pools
Warranty
1 year

Hayward Perflex D.E. Filter Lineup

Above-Ground Perflex D.E. Filters

Product Filter Area D.E. Charge Flow Rate Pump
Hayward Perflex D.E. Filter with Clamp 4 lb (this model) 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

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 40 sq ft 7 lbs 80 GPM

Hayward W3EC40AC Perflex D.E. Filter Frequently Asked Questions

Does the W3EC40AC include D.E. powder?

No. 4 lbs of pool-grade diatomaceous earth must be purchased separately. Add D.E. through the skimmer with the pump running after initial setup. Do not use food-grade, pest-control, or industrial D.E. Perlite is a compatible silica-free alternative.

What is the bump-to-clean process?

When 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, and restart. The Flex-Tubes compress and release, redistributing the D.E. cake so it recoats the tube surfaces. No water is discharged and no fresh D.E. is needed in most cases.

Is this filter-only, or does it include a pump?

Filter only. If you need a matched pump, the W3EC40C92S pairs this same filter with a 1 HP PowerFlo Matrix pump.

How does D.E. filtration compare to sand or cartridge?

D.E. filters to 2 microns — significantly finer than sand (20-40 microns) or most cartridge filters (10-15 microns). The tradeoff is that D.E. requires periodic recharging and the Flex-Tubes need occasional inspection and eventual replacement. The PerFlex bump design substantially reduces the frequency of full D.E. recharges compared to a conventional D.E. filter.

Hayward Perflex D.E. Above Ground Pool Filter with Clamp 4 lb Reviews

Trustpilot