RO System permeate pump question

[noaht]

Hello, I bought an Ispring RO system (RCC7P-AK) with a tank and booster pump. Installed it and everything is running well. Though I had read how a permeate pump improves your system in a few ways so I bought the ERP500 pump but I'm unsure how to install it. I understand the brine in and brine out ports and how to hook that up.

Where I'm confused is the permeate in and out ports on the pump. Currently my RO membrane permeate out goes to an inline check valve, then to a high pressure switch to some post filters and the tank. Do I take the tube that comes out of the high pressure switch and put that into the permeate in?

And do I need the ASV? Can someone explain why it is or isn’t needed for my system? I do have the ASV-ERP-JG just don't understand it fully.

Thank you!

 

[Bannerman]

A permeate pump (PP) eliminates virtually all of the pressure from the storage tank, from pushing back against the membrane. The resulting higher pressure differential across the membrane, will result in higher quality RO water (permeate), and will also permit faster production through the membrane. This will cause the storage tank to fill more quickly, thereby reducing the amount of brine water discharged to drain since the RO unit will operate for less time each day to satisfy the same amount of water production.

The pressure switch for the booster pump, should be sensing the pressure of the water in storage. As permeate is produced, the storage pressure will increase. Once the storage pressure has risen to a specific pressure, the tank will be essentially full so the system will not need to continue operating. With the pump's high pressure switch set to a lower pressure than the ASV cutoff, the pump will shut down before the ASV, but with the ASV suddenly sensing lower supply pressure, the ASV will stop all water flow once the booster pump is shut down.

A standard ASV, will stop production once the storage pressure has risen to ~60% of the supply pressure.

Although use of an ASV is not essential when a permeate pump is utilized, using an ASV is highly recommended, particularly when small amounts of water are regularly drawn.

Whenever the system is sitting idle, some of the TDS from the feed water in contact with the membrane, will migrate through the membrane, commonly referred to as TDS creep. Once the system is reactivated, initial production flow through the membrane will contain higher TDS compared to when the system has been operating for some time.

With a PP, but no ASV, the system will short cycle each time any amount of water is drawn whereas, an ASV will commence production when the storage pressure is 40% of incoming pressure, thereby causing the system to operate for longer once activated. As a result, TDS creep will be reduced, resulting in higher quality RO water.