Why install booster pump before 4th stage membrane:

Install the booster pump before stage1 is easier but the solenoid valve and pump may get dirty water and debris from water supply hence shorten the life of the solenoid valve and pump. Also the bottom 3 filters will not see high pressure to prevent bursting of filter housing. The pressure switch can be installed anywhere after the RO membrane on the pure water side. Either way works.

Continue

1 x	bulksf05, Koolermax Sediment Filter
1 x	5th or 6th Stage IC21 inline carbon filter (every 6 to 12 mons)
1 x	1/2" NPT Digiflow Digital Flow Meter count up total Water Gallon
2 x	Value Pack- Entire 3 Years of Replacement Filters Bundle K6ALK
1 x	Value Pack- Entire 3 Years of Replacement Filters Bundle RO585
1 x	Parts, Ro Water System Installation Parts Bag 1/4"
1 x	FPK, 6 pcs Fitting Pack Union Connector 3/8 x 1/4 inch
1 x	3rd stage C10 carbon block filter (replace every 6-12 months)
1 x	B2012, 20" Long Slim Filter Cartridge Housing RO260 RD322
1 x	WH-20, Whole House Water Treatment Carbon Block Filter System Bi
1 x	733, Built-in Pressure Gauge 0 to 150 psi for Koolermax RO syste
1 x	1st stage SF05 sediment filter (replace every 6-12 months)
1 x	4th stage TFC150 US membrane filter (every 2-3 yrs)M150 P/N3150
1 x	1044-K Male Connector 1/4 OD x 1/4 NPT Compression Fitting
1 x	Value Pack- Entire 3 Years of Replacement Filters Bundle K5
1 x	205, 2nd stage carbon block filter (replace every 12 months)
1 x	Special, Output Conversion Kit Convert from 1/4" to 3/8"
1 x	WH1134 Whole House Restaurant Filter System Sediment Carbon Big
1 x	Value Pack- Entire 3 Years of Replacement Filters Bundle K5150P
2 x	Wrench 2 pcs 566 Standard Filter Housing Opener Double Better
1 x	532b, PAE RO Water Storage Pressure Osmosis Tank Container 4G
1 x	3.CB2010, 3rd stage carbon block filter 20" inch for RD322 RO260
1 x	MK800, Maintenance kit for AR122, AR125, HK120, RD150, RO155
1 x	DM-1, Inline Dual TDS monitor (meter) for RO DI System DM1

View Cart	$1,931.99

1 x	bulksf05, Koolermax Sediment Filter
1 x	5th or 6th Stage IC21 inline carbon filter (every 6 to 12 mons)
1 x	1/2" NPT Digiflow Digital Flow Meter count up total Water Gallon
2 x	Value Pack- Entire 3 Years of Replacement Filters Bundle K6ALK
1 x	Value Pack- Entire 3 Years of Replacement Filters Bundle RO585
1 x	Parts, Ro Water System Installation Parts Bag 1/4"
1 x	FPK, 6 pcs Fitting Pack Union Connector 3/8 x 1/4 inch
1 x	3rd stage C10 carbon block filter (replace every 6-12 months)
1 x	B2012, 20" Long Slim Filter Cartridge Housing RO260 RD322
1 x	WH-20, Whole House Water Treatment Carbon Block Filter System Bi
1 x	733, Built-in Pressure Gauge 0 to 150 psi for Koolermax RO syste
1 x	1st stage SF05 sediment filter (replace every 6-12 months)
1 x	4th stage TFC150 US membrane filter (every 2-3 yrs)M150 P/N3150
1 x	1044-K Male Connector 1/4 OD x 1/4 NPT Compression Fitting
1 x	Value Pack- Entire 3 Years of Replacement Filters Bundle K5
1 x	205, 2nd stage carbon block filter (replace every 12 months)
1 x	Special, Output Conversion Kit Convert from 1/4" to 3/8"
1 x	WH1134 Whole House Restaurant Filter System Sediment Carbon Big
1 x	Value Pack- Entire 3 Years of Replacement Filters Bundle K5150P
2 x	Wrench 2 pcs 566 Standard Filter Housing Opener Double Better
1 x	532b, PAE RO Water Storage Pressure Osmosis Tank Container 4G
1 x	3.CB2010, 3rd stage carbon block filter 20" inch for RD322 RO260
1 x	MK800, Maintenance kit for AR122, AR125, HK120, RD150, RO155
1 x	DM-1, Inline Dual TDS monitor (meter) for RO DI System DM1

View Cart	$1,931.99