Converting RO to RODI filter, how does it work?

SteveG66 · Nov 1, 2022

I picked up a used reverse osmosis system that was I believe was a drinking water system, I will convert it to RODI but am confused by a few of the components: a low pressure switch after the sediment filter and before the carbon filter. There is a water valve between the last filter and RO booster pump which feeds a gauge and the RO membrane. From the RO membrane it tees off into a high pressure switch and a line going to a polishing filter. The waste line of the RO membrane goes to the polishing filter as well. I plan to eliminate the polishing filter and the tee's. What function do the high pressure and low pressure switches provide?

I'm not an engineer but was able to diagram the flow and equipment, the switches and both lines going into the polishing filter don't make sense to me.

I do have on order a BRS dual DI cartridge system and all new filters on its way to complete this system once I get it figured out.

Any help would be great.

For our interest: I am a 6 year reefer upgrading from a failed 33 gal cube to a 47 gal lagoon, still putting it together while the livestock hang out in a 20 gal long aquarium as a temporary living situation. Fortunately, I was able to save all the livestock and equipment, tank is in the trash. I figured it was time to step up my water quality game!!

Thanks in advance,
SteveG

mann1139 · Nov 1, 2022

Unless you are using this for drinking, get rid of the polish filter. That is where the DI filters go.

Agree on waste being mis-plumbed, it should go to drain.

Switches are for safety. May be able to remove unless pump wiring requires them.

SteveMM62Reef · Nov 1, 2022

High Pressure switch Shuts the Pump off, when the Outlet Valve is Closed. Low Pressure Switch is to Protect the Pump from running dry. Inlet water pressure drops, or loss of water. I’ve seen Sediment Filters Shred for Ice Machines, causing a mess. Personally I’d put the Pump Before the Sediment Filter, and put a RO/DI Strainer before the pump.

KStatefan · Nov 1, 2022

Go to Buckeye Hydro and look at hook up diagrams

SteveG66 · Nov 1, 2022

Thanks everyone for your advice, I'll get rid of the polishing filter and replace all of the filters which come tomorrow. I'll check Buckeye Hydros website as well.

Thanks again,
SteveG

SteveMM62Reef · Nov 2, 2022

Wonder if it would be Cheaper in the long run to just get a BRS RO/DI System, and put your Booster Pump and High/Low Pressure Safety Switches on it.

SteveG66 · Nov 2, 2022

SteveMM62Reef said:
Wonder if it would be Cheaper in the long run to just get a BRS RO/DI System, and put your Booster Pump and High/Low Pressure Safety Switches on it.

Steve, it probably would be less expensive in the long run but I've already gotten the system , and just received today all the replacement cartridges. It'll be just like new once I get it up and running. I just need to get to that point.

Thanks for the advice though,
SteveG

SteveG66 · Nov 2, 2022

Hopefully one last question, but you never know!!
Where does the restrictor go? I bought the BRS integrated flush valve and restrictor for a 75 gpd output which matches the RO membrane.

SteveG66 · Nov 2, 2022

Just went for it, and it works!! After the DI I'm getting O ppms TDS!!

Thanks everyone for your help, now to start making 50 gals of water for mix.

Next step is to move the tank and begin the cycling process.

Thanks again,
SteveG