Aquatec Permeate Pump

Aquatec Permeate Pump

“Permeate” is industry jargon for product water: the purified water that has passed through the reverse osmosis membrane, the water you will drink. The water that is rejected by the membrane, the waste water, is called “brine.”

A permeate pump is a special device for undersink reverse osmosis units that uses the hydro power of the brine, or waste water, to pack the permeate, or product water, into the storage tank.

Permeate Pump Ordering

Part #	Description	Price
RP100	Aquatec Permeate Pump. Includes instructions, screws and mounting bracket.	$77
RP101	Permeate Pump Upgrade. Aquatec Permeate Pump added to Black & White, Gold Series, Q Series RO unit at time of purchase.	$70

All prices include shipping!

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90% Shut-off Valve
for Permeate Pumps

Although the pump controls the unit completely and does not need a shut-off valve to shut down the unit, some prefer performance with a shutoff valve. There are special "90% shutoff valves" on the market sold to work with the permeate pump. It shuts the unit down when tank pressure reaches 90% of the inlet pressure. We haven't yet found a "90% shutoff valve" that we recommend.  You can run the unit with any standard shutoff valve and it will improve the unit's efficiency and the quality of the  product water, but you will still have only about 60% of your input pressure in the storage tank.

A standard reverse osmosis unit is controlled by an automatic shutoff system that shuts down water production when pressure in the storage tank reaches about 2/3 of the inlet water pressure. In other words, if your city water pressure is 60 pounds (psi), your reverse osmosis unit will stop producing and storing water when pressure in the storage tank reaches about 40 psi. For most household purposes, this is plenty of pressure and the RO unit will run wonderfully.

The same RO unit with a permeate pump and 60 psi coming in will continue to produce water until pressure in the tank reaches almost 60 psi. This is especially helpful for low-pressure installations. If, for example, you have a well system that provides only 40 psi, a standard RO unit will run,  but it won’t run well. The unit will shut down when tank pressure reaches 25 psi or so. With a permeate pump, the unit will put almost the full 40 psi into the storage tank.

What’s best about the permeate pump, though, is the increased efficiency. With a standard shutoff system, as the storage tank fills, the RO unit must push against an increasing amount of storage tank pressure. With the permeate pump, the unit is shielded from this pressure and the membrane works in a virtually pressure-free situation, even when the tank is almost full.

Permeate Pump Pros & Cons

Among the pump’s disadvantages are:

• A slight intermittent thumping noise—not really loud, but you’ll know when it’s running.

• It’s not easy to install on an existing RO unit (it makes new units no harder to install). We don’t recommend that you attempt to retrofit an existing RO unit to permeate pump operation unless you’re willing to go to a little trouble. We can provide instructions.

• A slight increase in TDS (total dissolved solids) reading under normal household operation. Because the pump starts the unit literally every time you take a thimble-full of water from the unit, overall rejection of dissolved solids may not be quite as good as with a standard unit. This is normally not a significant disadvantage, and it is offset by the greatly enhanced pressure performance, especially with low-pressure installations. And, if you take lots of water out of the tank at one time, you’ll actually experience improved TDS performance.

Advantages to the permeate pump are:

• The greatly improved water pressure from the RO tank, especially in low-pressure installations.

• No electricity used, and no electrical connection (as compared with electric booster pumps).

• Much greater efficiency. The unit does not have to push against the pressure of storage tank. The ratio of product water to waste water improves significantly.