4-Stage Under-Sink Reverse Osmosis System – Premium Water Filtration
Enjoy pure, great-tasting water straight from your dedicated faucet with this high-quality 4-stage reverse osmosis (RO) system. Designed for efficiency and reliability, this system removes contaminants while maintaining a low water waste ratio of just 1.25:1, making it more efficient than standard RO systems.
Why Choose This System?
The PSI-021-4S Reverse Osmosis System was developed to compete with imported Chinese RO systems, but without compromising quality. While it may not match their low prices, this system prioritises reliability, performance, and long-term durability.
✔ Compact Under-Sink Installation – Fits neatly under your sink with a dedicated faucet for easy access.
✔ Advanced 4-Stage Filtration – Utilises high-performance filters to remove impurities effectively.
✔ Genuine Dow Filmtec Membrane – Industry-leading 200 litres per day at 50 psi (350 kPa) and up to 300 litres per day at 87 psi, providing faster refills.
✔ No Electricity Required – Runs purely on water pressure using automatic shut-off valves and check valves.
✔ Low Waste Ratio (1.25:1) – Reduces water wastage compared to standard RO systems.
✔ Auto Shut-Off Function – Prevents unnecessary water waste by stopping flow when the storage tank is full.
✔ Certified & Compliant – All components meet Australian Standards and NSF certifications (042, 053, 058) for safety and performance.
✔ Optional Alkalizer (Re-Mineraliser) – Restores essential minerals and balances pH to neutral, counteracting the natural acidity of RO water.
How It Works: 4-Stage Filtration Process
🔹 Stage 1: 1-Micron Food-Grade Sediment Filter (U.S. Made) - Removes dirt, sand, and other physical particles.
🔹 Stage 2: Omnipure Coconut Carbon Block Filter (U.S. Made) - Reduces chlorine, chemicals, and odours. Rated for 37,000 litres of chlorine removal.
🔹 Stage 3: Reverse Osmosis Membrane (Dow Filmtec – U.S. Made) - Removes 96-98% of fluoride, heavy metals, and other impurities. Industry-standard Thin Film Composite (TFC) membrane ensures only pure H₂O molecules pass through.
🔹 Stage 4: Omnipure Coconut Carbon Post-Filter (U.S. Made) - Further purifies water, improving taste and removing organic compounds.
✔ Optional Alkalizer (Re-Mineraliser) – Uses crushed marble and limestone to restore essential minerals and neutralise acidity.
System Specifications & Features
- Premium Components – Includes a 550 kPa pressure-limiting valve with dual check valves (Watermark certified: AS1357-2, Licence No. 23133).
- Installation Options – Choice of ½” tee olive fitting, ¾” dishwasher adapter, or ½” easy-fit braided line flick mixer adapter.
- Easy Installation – Designed for the average handyman, installation takes 30-60 minutes.
- Minimum Required Pressure: 40 psi (280 kPa) (50 psi/350 kPa or higher is ideal).
- Main Filter Unit Size: 42 cm high × 35 cm wide × 14 cm deep.
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Storage Tank Options:
- Standard: 9L stainless steel tank (NSF Certified, exceeds drinking water guidelines).
- Alternative tank sizes available:
- 4.2L: 33 cm high × 20.5 cm diameter
- 9L: 39 cm high × 24 cm diameter
- 12L: 39 cm high × 27.5 cm diameter
Replacement Cartridges & Maintenance
🔹 Annual Cartridge Pack – Click [here] to order.
🔹 Reverse Osmosis Membrane (Replaced every 4 years) – Click [here] to order.
🔹 Re-Mineraliser Cartridge (If fitted, replaced every 2 years) – Click [here] to order.
