Rheem Preferred RHS32 vs Rheem Preferred Plus RHS42

Last updated: November 1, 2026

The Rheem Preferred Plus RHS42 rates 3.7 among 32,001 to 48,000 grains water softeners; the Rheem Preferred RHS32 rates 3.7 among up to 32,000 grains ones. The Rheem Preferred RHS32 costs $60 less ($489 vs $549).

Rheem Preferred RHS32 vs Rheem Preferred Plus RHS42

Prices were last checked November 1, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.

Scores side by side

These two sit in different size classes (32,001 to 48,000 grains and up to 32,000 grains), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.

Factor weightRheem Preferred Plus RHS42Rheem Preferred RHS32
Overall rating3.7/53.7/5
Value 30%76 $13.07 per 1,000 grains ($549, 42,000 grains)77 $15.28 per 1,000 grains ($489, 32,000 grains)
Salt efficiency 20%100 5,010 grains per lb of salt97 4,940 grains per lb of salt
Flow 15%32 9.9 gpm service flow32 7.9 gpm service flow
Warranty 25%22 3 years on the valve, 10 years on the tanks22 3 years on the valve, 10 years on the tanks
Certification 10%100 certified to NSF/ANSI 44100 certified to NSF/ANSI 44

Specifications

Rheem Preferred Plus RHS42Rheem Preferred RHS32
Capacity
Rated capacity42,000 grains32,000 grains
Resin1.2 cu ft0.9 cu ft
Service flow9.9 gpm7.9 gpm
Salt efficiency5,010 grains per lb4,940 grains per lb
Highest hardness140 gpg105 gpg
Highest iron11 ppm8 ppm
Control
ValveRheem demand valveRheem demand valve
Regenerates on demandYesYes
App or remote monitoringNoNo
Bypass valve includedYesYes
Certification and warranty
NSF/ANSI 44YesYes
Valve warranty3 years3 years
Tank warranty10 years10 years

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