Rheem Preferred Plus RHS42
A well rounded certified softener for a family of up to six on hard city or well water.
Home Depot $549$549
3.4/5
A good value 40,000 grain softener for a family of three to five, with certified salt efficiency and strong iron handling.
- 40,000 grainsCapacity
- 7.6 gpmService flow
- 5,094 gr/lbSalt efficiency
- YesNSF/ANSI 44
Check price at Blain's Farm & Fleet$579.99
Price checked November 1, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Salt efficiency above 5,000 grains per pound at the low setting cuts salt bills
- Handles hard well water up to 125 gpg with up to 10 ppm iron
- NSF certified for capacity and efficiency
Cons
- Service flow under 8 gpm can drop pressure when two showers and a washer run at once
- Short one year full parts warranty without the cleanser plan
The Whirlpool WHES family
Every Whirlpool WHES model we rank, smallest first. Ratings compare each against its own size.
| Model | Capacity | Rating | Price |
|---|---|---|---|
| Whirlpool WHES30 | 30,000 grains | 3.6/5 | $469.99 |
| Whirlpool WHES40 (this one) | 40,000 grains | 3.4/5 | $579.99 |
| Whirlpool WHES48 PRO | 48,000 grains | 3.8/5 | $679.99 |
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
Specifications
| Model number | WHES40 |
|---|---|
| Capacity | |
| Rated capacity | 40,000 grains |
| Resin | 1.1 cu ft |
| Service flow | 7.6 gpm |
| Salt efficiency | 5,094 grains per lb |
| Highest hardness | 125 gpg |
| Highest iron | 10 ppm |
| Control | |
| Valve | Whirlpool demand valve |
| Regenerates on demand | Yes |
| App or remote monitoring | No |
| Certification and warranty | |
| NSF/ANSI 44 | Yes |
| Valve warranty | 3 years |
| Tank warranty | 10 years |
Alternatives in this size
Aquasana SimplySoft 40K
A certified, salt efficient cabinet softener for a family of up to five on city water. Pick it over cheaper uncertified units if you want verified salt savings.
Amazon $749$749
Aquasure Harmony 48K
A budget metered softener sized for a typical family with hard water. It costs little per grain, but its capacity and salt use are not independently verified.
Amazon $629.99$629.99
Compare
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