Kohler Aquifer RO (K-22155) review
By Daryna Klochko · Published · Specs checked Oct 15, 2026 · 
Scores 9.25/10, tied for 10th of the 20 RO systems we track. At $648.75 it costs more than the category median of $459.99. IAPMO lists it for Chlorine, Chloramine, Lead, Cysts, VOCs, PFOA/PFOS, TDS, Arsenic, Fluoride, one of 12 RO systems out of 20 with a certifier listing for a health claim. Its 90-day return window is 3 times the 30-day category median.
A long warranty: 5 years, the longest stated among the 20 RO systems
Running costs matter: about $656 a year in cartridges, 3.2 times the category median
- Price
- $648.75
- Certified for
- Lead · Cysts · VOCs +12
- Flow
- 0.5 gpm
- Cartridge life
- 230 gal
- Cost per year
- $656
- Warranty
- 5 years limited
Certification
Listed by IAPMO under NSF/ANSI 42 · 53 · 58 · 401 · P231 for Chlorine, Chloramine, Lead, Cysts, VOCs, PFOA/PFOS, TDS, Arsenic, Fluoride, checked Oct 15, 2026. Search the IAPMO listings
- Chlorine
- Chloramine
- Lead
- Cysts
- VOCs
- PFOA/PFOS
- TDS
- Arsenic
- Fluoride
The contaminants or other substances removed or reduced by this water treatment device are not necessarily in your water. Listing checked on Oct 15, 2026. What a listing means and what it doesn't
Specs and sources
Checked Oct 15, 2026 · source under each valueFiltration
Cartridges and install
Buying
Warranty, returns and shipping
90 days from shipment (kohler.com, new and saleable).
Warranty: 5 years limited. Returns: 90 days from shipment (kohler.com, new and saleable). Shipping: not stated by the brand. Source: Kohler data sheet, checked Oct 15, 2026.
Source: Kohler data sheet, checked Oct 15, 2026.
Compared with similar RO systems
All 20 RO systems →| Model | Price | Certified for | Cost per year | Warranty | Score | Where to buy |
|---|---|---|---|---|---|---|
| A. O. Smith AOS-DFRO800 Tankless Reverse Osmosis | $474.99 | TDS | $290 | 2 years limited | 9/10 | Check price → |
| Brio G20-U ROSL700 Tankless Reverse Osmosis System | $499.99 | Brand claims only | $340 | 1 year (limited) | 8.75/10 | Check price → |
| APEC Water ROTL-A1000 Tankless Reverse Osmosis | $599 | PFAS · TDS | $192 | 1 year (limited) | 9.75/10 | Check price → |
| Kohler Aquifer RO (K-22155)THIS MODEL | $648.75 | Lead · Cysts +13 | $656 | 5 years limited | 9.25/10 | Check price → |
| Pentair FreshPoint GRO-575 5-Stage Reverse Osmosis | $669.29 | Lead · Cysts +14 | $238 | 1 year | 9.25/10 | Check price → |
What owners say
Checked Oct 15, 2026Reviews only on the brand's own site. In our score this is 1.75 of 2 points. How we score
Store ratings change over time; the date shows when we checked.