Compare Fleck 5600SXT vs WHES40
Fleck 5600SXT vs Whirlpool WHES40 Repairable Valve or Sealed Unit
WQA lists the Fleck 5600SXT at 10.8 gpm in its 1.0 cu ft configuration. NSF lists the WHES40 at 7.6 gpm. The Whirlpool tells you its capacity at each dose. With the Fleck, you choose the dose.
Where to buy · Fleck 5600SXT: $876.00 (1.0 cu ft) on the seller's site, checked Oct 22, 2026. No retailer link yet.
Where to buy · WHES40: price not yet verified; sold through retailers. No retailer link yet.
Short answer: Pick the Fleck if you want a standard, serviceable valve and more flow, and you’re happy to set the salt dose yourself. Pick the WHES40 for a plug-in install with certified salt figures out of the box.
Capacity by Salt Dose
Fleck 5600SXT
No capacity-by-dose table published. Rated 35,000 grains at an unstated dose.
WHES40
Capacity per regeneration at each salt dose the maker publishes (Whirlpool manual (2023), source). We don't fill in doses between these points. The efficiency rating (5,094 grains per lb) applies only at the 3.4 lb dose.
Certification Side by Side
| Fleck 5600SXT | WHES40 | |
|---|---|---|
| Status | WQA listed | NSF listed |
| Certifier and standard | WQA NSF/ANSI 44 | NSF NSF/ANSI 44 |
| Certified flow | 10.8 gpm (5600 SXT-1.0) | 7.6 gpm |
| Salt efficiency | not published | 5,094 gr/lb at 3.4 lb |
| Sold as | 35,000 grains | 40,000 grains |
| At lowest published dose | not published | 17,300 grains at 3.4 lb |
Specs Side by Side
| Fleck 5600SXT | WHES40 | |
|---|---|---|
| Service flow (maker) | 10 gpm peak (1.0 cu ft kit) source | 7.6 gpm source |
| Resin | 1.0 cu ft (also 0.75, 1.5, 2.0) source | 1.14 cu ft source |
| Max hardness | not yet verified | 125 gpg source |
| Iron | not yet verified | 10 ppm clear-water iron source |
| Pressure | not yet verified | 20–125 psi source |
| Warranty | 5-year valve, 10-year tank source | not yet verified |
| Price | $876.00 (1.0 cu ft) source | not yet verified |
Where They Differ
Flow. 10.8 gpm certified for the Fleck 1.0 cu ft, 7.6 gpm for the WHES40.
Salt data. The WHES40 publishes three doses: 17,300, 31,600 and 40,000 grains. The Fleck kit lists only a 35,000-grain “max capacity (new)”.
California. The WHES40 meets California’s efficiency requirement on its NSF listing. WQA doesn’t list the Fleck for it.
Service. The 5600SXT is a standard valve with parts sold widely. The WHES40 is a single sealed cabinet.
Common Questions
What capacity does a 1.0 cu ft Fleck give at low salt?
US Water Systems doesn’t publish a dose table. A generic resin data sheet puts 1 cu ft at 15,000 grains at 3 lb and 30,000 at 10 lb (Neo-Pure data sheet). That’s resin data, not a Fleck certification.
Is a retailer's Fleck kit the certified one?
WQA lists Pentair’s own 5600SXT configurations. A kit matches only if it’s built the same way, and the seller doesn’t say.
Full sheets: Fleck 5600SXT · WHES40. Or size your own in the calculator.