Quick Answer: EcoWater is the oldest dealer-only softener brand this site reviews — founded in 1925 — and the only one owned by Berkshire Hathaway, through the Marmon Group, which Warren Buffett’s company has fully owned since 2013. Like every brand in this category, no price appears anywhere, including on ecowater.com or Costco’s own EcoWater program page. Aggregated dealer-quote reports put the ERR3700 refiner at $3,600 to $6,000 installed and the flagship ERR3702 at $6,000 to $10,000, with Costco members getting a 10% Shop Card back after install. That’s real hardware and a genuinely deep-pocketed parent company behind the warranty — just know the numbers, and that this is the same dealer network this site already flagged behind both Costco’s and Home Depot’s whole-house listings, before the in-home demo starts.
A brand old enough to predate the modern water-softener category itself, backed by the same company that owns See’s Candies and GEICO, is a different pitch than most dealer-only softener sales visits lead with. This guide decodes EcoWater’s current product tiers, publishes the real numbers dealers and Costco members have reported paying, and puts the warranty and ownership history next to the alternatives so you can walk into the quote already informed.
Who actually makes EcoWater
EcoWater Systems was founded in 1925, making it roughly two decades older than RainSoft’s parent company Aquion (1953), more than three decades older than Puronics (1947), and a full century older than most of the smart-home softener marketing that now surrounds the category. EcoWater is a member of the Marmon Group, a Chicago-headquartered collection of roughly 140 independently operated manufacturing and service businesses. Marmon was founded by brothers Jay and Robert Pritzker in 1953; Berkshire Hathaway acquired a controlling stake in Marmon in 2007 and took full ownership in 2013. That makes EcoWater the only brand in this site’s dealer-only softener lineup backed by a holding company built around insurance float and long-term industrial ownership, rather than a publicly traded water-heater maker (Hague, owned by A.O. Smith since 2017), a pump manufacturer (Puronics, owned by Franklin Electric since 2021), an industrial conglomerate (RainSoft, owned by Pentair since 2019), or a Swedish holding group (Kinetico, owned by Axel Johnson since 2006).
EcoWater distributes through more than 250 independent dealers across North America, part of a wider network reaching 50-plus countries worldwide under the same Marmon/EcoWater organization. Every residential system starts with a free in-home water test, is sized to household demand and hardness, and is installed and serviced by that local dealer — the same closed-distribution model this site has already documented for Kinetico, Culligan, and RainSoft.
ECR vs ERR, decoded
| Feature | ECR 3700 series | ERR 3700 / ERR3702 |
|---|---|---|
| Function | Softening only | Softening + activated-carbon chlorine/odor reduction |
| Water source | Municipal or well | Municipal or well |
| Media warranty | 5 years | Lifetime (original owner) |
| Tank warranty | Lifetime against rust/failure | Lifetime against rust/failure |
| Valve body warranty | 10 years | 10 years |
| Electronics warranty | 7 years | 7 years |
| Reported installed price* | Not separately published | ERR3700 about $3,600-$6,000 · ERR3702 about $6,000-$10,000 |
*Aggregated dealer-quote and owner reports via Mid Atlantic Water’s EcoWater cost guide and Costco-program buyer accounts; EcoWater publishes no pricing on ecowater.com or its Costco program page.
The tier gap is straightforward: an ERR system does everything an ECR does, plus a carbon layer in the same tank for chlorine taste and odor, at a higher quoted price. The bigger warranty gap sits inside the ERR line itself — ERR-series media is covered for life, while ECR-series media is covered for 5 years — which is worth asking a dealer to itemize before assuming “EcoWater” means one blanket warranty tier across every model.
What real owners and Costco members actually pay
EcoWater doesn’t publish a number on ecowater.com, and Costco’s own EcoWater program page works the same way — it books a free in-home consultation, not a checkout. Aggregated dealer-quote and owner reports collected via Mid Atlantic Water’s EcoWater cost guide put the ERR3700 refiner at roughly $3,600 to $6,000 installed, and the flagship ERR3702 at $6,000 to $10,000. Costco members buying through EcoWater’s warehouse-club program land in that same higher band — one documented Southern California quote came in around $5,000 installed plus a $500 Costco Shop Card, while a bundled softener-plus-reverse-osmosis Kansas quote totaled $5,900 with first-year service included. Costco’s standard rebate is a Shop Card worth 10% of the qualified purchase, issued after installation — not an instant discount at time of sale. This matches the $3,600-to-$10,000 range this site’s own Costco water filter guide already documented for the identical EcoWater program, where EcoWater also carries a 2.6-star Yelp average and 2.9 on Trustpilot.
For comparison, here’s what published-price alternatives cost for comparable softening hardware:
| System | Type | Published price | Warranty |
|---|---|---|---|
| EcoWater ERR3700 (quoted) | Softener + carbon, computer-controlled, installed | $3,600-$6,000 | Lifetime media/tank, 10 yr valve, 7 yr electronics |
| EcoWater ERR3702 (quoted) | Flagship softener + carbon, installed | $6,000-$10,000 | Lifetime media/tank, 10 yr valve, 7 yr electronics |
| SpringWell SS1 | Single-tank, metered, DIY/plumber | $1,495 | Lifetime (tank/valve) |
| Fleck 9100SXT twin-tank | Twin-tank, metered, DIY/plumber | $1,300-$2,200 | 5 yr valve |
| Fleck 5600SXT 48k | Single-tank, metered, DIY/plumber | $650-$900 | 5 yr valve |
The gap between roughly $4,800 (ERR3700 midpoint) and roughly $800 for functionally similar softening hardware is the price of the dealer channel: a professional water test, sizing, installation, local service, and a warranty backed by one of the largest holding companies in the world. Whether that backing is worth $3,000-plus to you is a fair question to answer with real numbers, not a sales pitch, in front of you.
EcoWater ERR3702 — the flagship refiner
EcoWater ERR3702 Premium Water Refiner
- Softens water and reduces chlorine taste/odor in a single tank, for either municipal or well-water supplies.
- Filtering media carries a lifetime warranty for the original owner — the same tier as the tank itself.
- Computer-controlled valve regenerates on measured demand, not a fixed clock, so a light-use week doesn't waste salt.
- Backed by EcoWater's 250-plus-dealer North American network and, ultimately, Berkshire Hathaway's Marmon Group — the deepest-pocketed parent company in this category.
Replacement filters on time, every time — Prime ships them free in two days. Try it free for 30 days.
You can’t order an ERR3702 online — it’s dealer-quoted and dealer-installed only — but testing your own water hardness before the in-home visit means “you have very hard water” is a fact you already know, not a finding the dealer hands you at the same moment as the quote.
EcoWater ERR3700 — the standard refiner
EcoWater ERR3700 Water Refining System
- Same lifetime media and tank warranty tier as the ERR3702, at the lower end of EcoWater's quoted install range.
- Auto-adjusts regeneration based on measured household water use rather than a fixed schedule.
- Sized for typical single-family residential demand — the standard first quote for most homes.
- The ECR3700 (softening-only, no carbon layer) sits below this in EcoWater's lineup with a shorter 5-year media warranty, if chlorine reduction isn't a priority.
The honest framing: the ERR3700 is solid, century-old-brand hardware, but it competes at a price point where several published-price softeners with 5-year-plus warranties also live. The case for paying EcoWater’s premium rests on the professional water test, the local dealer relationship, and the Berkshire Hathaway-backed warranty — not on hardware unavailable anywhere else.
EcoWater vs the alternatives
Vs. RainSoft and Kinetico. All three are dealer-only, quote-by-visit brands with overlapping $3,000-to-$10,000+ installed ranges. RainSoft’s limited lifetime warranty covers tank, valve and electrical parts in one blanket tier; EcoWater splits coverage by component (lifetime tank and ERR media, 10-year valve, 7-year electronics), which is arguably more transparent even if the headline sounds less sweeping. Kinetico’s non-electric, twin-tank valve never runs out of soft water mid-regeneration — EcoWater’s computer-controlled valve is electric and single-tank on the ERR3700/3702, so a regeneration cycle briefly bypasses softening the way RainSoft’s does too.
Vs. Hague and Puronics. Two more dealer-only, no-published-price brands — Hague (A.O. Smith-owned since 2017, founded 1960) and Puronics (Franklin Electric-owned since 2021, founded 1947) — both younger brands than EcoWater’s 1925 founding, with real-world installs in the same broad $3,000-$10,000-plus range.
Vs. published-price online systems. This is the real decision for most buyers. A SpringWell SS1 at $1,495 with a lifetime tank-and-valve warranty, plus a few hundred dollars of plumber time, delivers softening performance comparable to an EcoWater ERR3700 quote at roughly a third of the money — the trade is that sizing, installation and service become your responsibility instead of a dealer’s. On well water with iron or sulfur present, professional sizing carries more weight, which is where dealer brands like EcoWater genuinely earn part of their premium.
Vs. not softening at all. If the complaint is scale on fixtures rather than soap performance, a salt-free conditioner treats scale without salt bags — but conditioned water still tests hard on a strip, and no dealer selling one should claim otherwise.
How to walk into the quote
- Test your own water first. A hardness strip test on city water, or a full water test kit on a well, means you already know your grains per gallon before the dealer’s demo does.
- Get three numbers: an EcoWater quote (through Costco or a direct dealer), a RainSoft or Kinetico quote, and one published-price online system sized for your hardness. Every dealer in this category negotiates differently once they know a competing number exists.
- Ask the dealer to itemize the warranty by component — EcoWater’s tiers differ by part (lifetime tank and ERR media, 5-year ECR media, 10-year valve, 7-year electronics) — and confirm labor coverage for service calls in writing, since no residential tier covers labor automatically.
- If quoting through Costco, ask exactly what qualifies for the Shop Card rebate — it’s a 10% card issued after installation, not a discount applied at the time of sale.
- Request equipment and installation as separate line items. A single bundled number hides where the margin sits.
Bottom line
EcoWater is the oldest dealer-only softener brand this site reviews — founded in 1925 — and the only one owned by Berkshire Hathaway, through the Marmon Group Warren Buffett’s company has fully owned since 2013. That longevity and financial backing are real, and the component-by-component warranty (lifetime tank and ERR media, 10-year valve, 7-year electronics) is genuinely detailed. What it doesn’t come with is transparency: no published price on ecowater.com or Costco’s own EcoWater program page, and installed quotes running $3,600 to $10,000 for hardware a published-price system delivers for under $2,000. Bring your own hardness number, bring a competing quote from RainSoft or Kinetico, and ask the dealer to justify the premium for your water specifically — not water, or a century of brand history, in general.