This Reverse Osmosis Undersink 4 Stage model PSI-021-4P-GM is a premium low waste unit featuring the exclusive membrane flushing.

It has the Dow Filmtec 300 litre per day TFC membrane, the 300 litres is rated at 50 psi (350 kpa) but will produce up to 450 litres per day higher pressures, what this means is the system will fill faster than most systems on the market. This system has an auto shut-off device that closes off the in-feed supply when the storage tank has filled.

The PSI-021-4P-GM has twin pressure gauges to monitor the pressure difference between the mains in-put pressure and the pressure being applied to the membrane after the two pre-filters, this allows you to monitor what is happening within the system from the outside.

Click here to down load a sample of the installation instructions pdf format

This system also comes with a TDS meter (total dissolved solids) which measures impurities in water in parts per million (ppm), this allows you to easily measure the success of the membrane and re-assure you all is working correctly.

All components are NSF certified to standards 042, 053 & 058

 Highest Quality Pentek (Ametek) US housings, standard size 10 inch (9 ¾" (248mm) NSF certified (worlds leading certification authority) NSF/ANSI standard 042 certification, also tested and certified to Australian Standards 3497, housing no 158179

Removes 92 to 95% of Fluoride, for membrane treatment rates click here.

1 Micron food grade polyspun sediment filter 9 ¾" (248mm) (standard size) U.S. made

Matrikx CTO/2 quality carbon cartridge 9 ¾" (248mm) 22,500 litres chlorine rating, U.S. made

Genuine Omnipure CL10RO- Coconut carbon post filter, highest quality possible. U.S. made

Genuine Dow Filmtec TFC Membrane (standard by which all other membranes are measured)

Main filter unit size, 42 cm high, 35 cm wide & 14 cm deep.

9 litre stainless steel storage tank (exceeds drinking water guidelines) NSF Certified. If space is an issue we also offer a 4.2 litre or 12 litre tank, click here for tank details.

Premium systems now have the lowest waste ratio of all systems on the Australian market, using a Patented combination membrane flushing valve/flow restrictor means the waste ratio is about 50% less waste than other brands, waste ratio is now about 1 to 1. click here to obtain more information about waste ratios

Installation choice 1/2" tee olive fitting, 3/4"dishwasher adapter or 1/2" easy fit braided line flick mixer adapter, our systems take the average handyman 1/2 to 1 hour to install

Mains connect systems click here to view how each are installed

600 kpa pressure limiting valve, genuine Tomlinson Stainless Steel  dedicated faucet

Housing spanner to ease cartridge changes.

Replacement set of cartridges.(3) $60.00, less 20% if a replacement set is ordered with the unit.

10 year warranty Click here for selection Advice

PSI Systems are Better Than Other Brands, click here to find out why

Typical Mineral removal, not all are listed.

Chemicals that system will treat for

Alachlor, Atrazine, Benzene, Bromochloroacetonitrile2, Bromodichloromethane1, Bromoform1, Tetrachloride, Chlorobenzene, Chlorine, Chloroform1, Chlorodibromomethane1, Chloropicrin, 2,4-D, Dibromoacetonitrile2, DBCP, Dichloroacetonitrile2, o-Dichlorobenzene, p-Dichlorobenzene, 1,2-Dichloroethane, Pentachlorophenol, Simazine, Styrene, 1,1,2,2-Tetrachloroethane, Tetrachloroethylene, Toluene, 2,4,5-TP (Silvex), Tribromoacetic Acid, Trichloroacetonitrile2, 1,2,4-Trichlorobenzene, 1,1,1-Trichloroethane, 1,1,2-Trichloroethane, Trichloroethylene, 1,1,1-Trichloro-2-Propanone3, 1Trihalomethanes, m-Xylene, p-Xylene, 1,1-Dichloroethylene, cis-1,2, Dichloroethylene, trans-1,2-Dichloroethylene, 1,1-Dichloro-2-Propanone3, 1,2-Dichloropropane, cis-1,3-Dichloropropylene, Dinoseb, Endrin, Ethylbenzene, EDB, 2Haloacetonitriles (HAN), 3Haloketones (HK), Heptachlor, Heptachlor Epoxide, Hexachlorobutadiene, Hexachlorocyclopentadiene, Lindane, Methoxychlor