The EcoPure EP42 is certified by NSF International to NSF/ANSI 44 for hardness reduction and salt efficiency. It’s a one-piece, demand-regenerating softener rated at 42,200 grains and 8.2 gallons a minute, and handles up to 110 grains per gallon of hardness.
The catch: Its flow is a step up from smaller softeners but still below high-flow models, and its iron rating is EcoPure’s own, not certified.
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Is the EcoPure EP42 a good water softener?
Yes. NSF International certifies the EcoPure EP42 to NSF/ANSI 44, the standard for residential ion-exchange softeners, for hardness reduction and as efficiency rated. That means its published capacity was verified, and it removes at least 3,350 grains of hardness per pound of salt while using no more than 5 gallons of water per 1,000 grains. EcoPure rates it at 5,090 grains per pound, a little above the 5,040 Kenmore gives for the Kenmore 350 we also review.
It’s a true softener. Resin swaps the calcium and magnesium in your water for sodium, so scale stops forming on fixtures, glass, shower doors and inside the water heater. It regenerates on demand: the control tracks the water you use and recharges only when it needs to. The resin tank and the salt tank share one cabinet, and the bypass valve comes in the box.
What sets it apart is size. With 1.09 cubic feet of resin and a rated 42,200 grains, it goes longer between regenerations than a 32,000-grain softener on the same water, and it handles up to 110 grains per gallon (gpg) of hardness. Its rated flow of 8.2 gallons a minute is a step up from the Kenmore 350’s 7.2, though a home running several showers and appliances at once is still better served by a higher-flow softener.
You have hard city or well water, very hard water or a mid-size household, and want a certified, salt-efficient softener with capacity to spare.
You have a large home with several bathrooms in use at once, need certified iron removal, or your area restricts salt-discharge softeners.
How it scored
For softeners, treatment performance takes the place of contaminant reduction and carries the most weight in the overall score. How we checked · How we score
What does it remove?
Hardness, and that’s its certified job. It isn’t a filter for chlorine, lead or PFAS.
| What you want | EcoPure EP42 | Notes |
|---|---|---|
| Hardness (calcium, magnesium) | Certified | NSF International, NSF/ANSI 44 |
| Salt efficiency | Certified | Efficiency rated; EcoPure rates it at 5,090 grains per pound at the 3.3 lb setting |
| Clear-water iron | Up to 11 ppm | EcoPure’s limit, backed by its own lab data, not a certified claim |
| Barium, radium | No claim | Some certified softeners carry these; this one doesn’t |
| Chlorine, lead, PFAS | No | Not a filter |
| Bacteria, viruses | No | Not for unsafe water |
Source: NSF International’s NSF/ANSI 44 listing (Water Channel Partners, Ecopure EP42) and EcoPure’s EP31 and EP42 installation and operation manual. See our hard water guide and iron guide.
How much salt does it use?
About 3 pounds per 1,000 gallons at 15 gpg. At its rated setting it removes 5,090 grains of hardness per pound of salt, so your salt use depends on how hard your water is and how much you use. The table assumes the home softens 60,000 gallons a year, about 165 gallons a day.
| Your hardness | Salt per 1,000 gallons | Salt per year | 40 lb bags a year |
|---|---|---|---|
| 10 gpg | 2.0 lb | About 118 lb | About 3 |
| 15 gpg | 2.9 lb | About 177 lb | About 4.5 |
| 20 gpg | 3.9 lb | About 236 lb | About 6 |
Our calculation from EcoPure’s rated 5,090 grains per pound, which EcoPure says is valid only at the minimum 3.3 lb salt dose; the control picks the dose at each regeneration, so real use can be higher. To convert mg/L of hardness to gpg, divide by 17.1.
Each regeneration uses about 2.3 gallons of water per 1,000 grains at the minimum salt dose, and 40.6 gallons at the maximum. EcoPure recommends nugget, pellet or coarse solar salt and advises against rock and block salt. Using its EPCL softener cleaner about every four months also extends the parts and labor warranty from one year to five.
Pros and cons
What we liked
- Certified to NSF/ANSI 44 by NSF International
- Efficiency rated: 5,090 grains per pound (EcoPure)
- 42,200 grains of rated capacity, 1.09 cubic feet of resin
- Up to 110 gpg hardness and 11 ppm clear-water iron
- 10-year warranty on the tanks
What to know
- 8.2 gpm is below high-flow softeners
- Iron rating is EcoPure’s own, not certified
- Five-year parts warranty depends on regular cleaner use
- Needs a drain, an outlet and cold-water plumbing
- Adds sodium to softened water
Specifications
- Model
- EcoPure EP42 (model code E42P; retail models EP42007 and EP42023)
- Type
- Salt-based ion-exchange softener, one-piece cabinet
- Capacity
- 16,600 grains at 3.3 lb salt; 35,300 at 10.3 lb; 42,200 at 17.4 lb
- Flow rate
- 8.2 gpm rated, 14.9 psi pressure drop
- Resin
- 1.09 cubic feet
- Water limits
- Up to 110 gpg hardness, 11 ppm clear-water iron
- Operating range
- 40 to 120°F; 20 to 125 psi
- Plumbing
- 1 inch NPT connections
- Size
- 48 inches tall, 15 x 20.5 inch footprint
- In the box
- Softener, bypass valve, drain hose and fittings, hardness test strip
- Power
- 24 V plug-in supply, standard outlet
- Certification
- NSF International: NSF/ANSI 44, with NSF/ANSI/CAN 372 noted on the listing. EcoPure also lists CSA B483.1 by WQA
- Warranty
- 1 year parts and labor (5 years with EcoPure’s cleaner program), 3 years control board, 10 years tanks
Alternatives worth considering
Kenmore 350
Aquasana SimplySoft
Common questions
Who makes the EcoPure EP42 water softener?
NSF International lists it under Water Channel Partners of Eagan, Minnesota, the same listee as the Kenmore 350. The certification covers the EP42 for hardness reduction and salt efficiency at a rated 8.2 gallons a minute.
EcoPure EP42 vs Kenmore 350: which should I buy?
The EP42 holds more resin and rates 42,200 grains and 8.2 gallons a minute, against the Kenmore 350’s 32,100 grains and 7.2. Both are certified to NSF/ANSI 44 and almost equally salt-efficient. Pick the EP42 for very hard water or more people; the Kenmore costs less for a smaller home.
What’s the difference between the EP42 and the EP31?
Size. The EP31 is the smaller model, rated at 31,300 grains and 7.2 gallons a minute with 0.81 cubic feet of resin. Both are certified to NSF/ANSI 44 for hardness reduction and efficiency, and both rate 5,090 grains per pound of salt at the lowest setting.
Can I install it myself?
Yes, if you’re comfortable working on your main water line. The bypass valve and drain fittings come in the box, and it connects to 1 inch plumbing. You need a floor drain or standpipe and a standard outlet. Check your local plumbing code, since some areas require a licensed plumber.
Does softened water add sodium?
Yes. A sodium-based softener raises the sodium content of the water, and water for drinking or cooking doesn’t necessarily need to be softened, according to Virginia Tech’s household water quality program. If you’re watching sodium, drink from a reverse osmosis tap. See our sodium guide.
Can I use it on well water?
Yes, if the well water is safe to drink. EcoPure rates it for up to 11 ppm of clear-water iron and 110 gpg of hardness, though the iron rating isn’t certified. Test the well first, and treat bacteria, sulfur or high iron separately. See our well water guide.
The bottom line
The EcoPure EP42 is a certified, very salt-efficient softener with 42,200 grains of rated capacity, and it handles very hard water. It’s a good fit for mid-size homes and hard well or city water; large households with heavy simultaneous use should look at a higher-flow softener.
For the other ways to deal with hard water, see our best water filter for hard water guide.
- Certifier listings: NSF International, NSF/ANSI 44, Water Channel Partners (Eagan, MN): Ecopure EP42, 8.2 gpm, hardness reduction and efficiency rated; listing section notes NSF/ANSI 372.
- Also searched: NSF International (EcoWater Systems LLC, NSF/ANSI 44): no EcoPure rows. NSF International (E42P model code): not listed under that number. WQA and IAPMO R&T: directories could not be reached on 30 Oct 2026.
- Maker documents: EcoPure EP31 and EP42 installation and operation manual (7393268 Rev. F); EcoPure EP42 product page.
- Independent lab tests: None used.
Sources
- NSF International NSF/ANSI 44 listings: Water Channel Partners, Ecopure EP42 (checked 30 Oct 2026)
- EcoPure EP31 and EP42 installation and operation manual (7393268, Rev. F)
- EcoPure EP42 42,000 grain water softener product page
- Virginia Tech, Virginia Household Water Quality Program: Hardness in household water (442-664)
Prices as of November 1, 2026. Product prices and availability are accurate as of the date/time indicated and are subject to change. As an Amazon Associate we earn from qualifying purchases.