Booster Pumps - How do they work?

What does a booster pump do? And, do I need one for my RO or RO/DI system? These are questions that we frequently receive from our customers.  

An RO Membrane works by forcing water through layers of membrane material. It is necessary to have the proper water pressure to make sure purified water can be pushed through the layers.

65-80 PSI is the most ideal pressure range for the operation of the membrane. If your system does not have a pressure gauge, we highly recommend adding one. The higher the pressure, the more quickly water is made and the more efficiently the RO membrane works. Higher than 80 PSI, over-pressure related issues may develop, such as; leaking fittings, canisters, valves or ballooned membranes.  

The more-common issue; however, is too low of a water pressure. The lower the water pressure, the slower the water is produced and the higher the amount of water the system wastes as the system has trouble pushing water through the RO Membrane. Below 40 PSI, you may not have any water production at all. We typically recommend adding a booster pump if your water is below 45 PSI.


If the TDS of your water is above 500ppm, adding a booster pump is also a good idea as it will help to increase water production and reduce the amount of water wasted. 

A Booster Pump helps to increase the water pressure by utilizing diaphragms to boost the pressure of the water. Water from your tap floods the outer chamber of the pump. Inlet diaphragms sucks water into a center chamber while an outlet diaphragm pushes water out the outlet of the pump. You can think of them like toilet plungers facing opposite directions working in unison to pull and push water; concentrating the water stream and increasing water pressure.  

Most booster pump systems will include pressure solenoid(s) to ensure that the pump only turns on when it needs to. Our booster pump kits included high-pressure solenoid switches so the pumps shut off automatically when you shut off the product water with a valve, or your water reservoir /  drinking water bladder tank is full.