my upgrade journal/journey

[UncommonSense]

its several years old

Ah, and had been sitting to dry out for a few months!

I’d guess the RO membrane had water dry out inside its housing, caking the membrane in hard water deposits…

Once you started running it again, these deposits took a while to dissolve back into solution completely; hence the slowly dropping, still high TDS reading post-RO membrane!

a BRS 75 special. and i had added that top filter thing that is supposed to aid in reducing waste water.

I’m honestly not sure what you mean by this….

Are you referring to changing the flow restrictor, swapping to an auto flush kit, or adding a second RO membrane/housing?

— perhaps just get a picture of what’s going on up on top of your RO system if you aren’t sure?

 

[smitten with ocean life]

no, it never sat dry. ive been using it for a long time! i just meant it sits outside because we are in a moderate climate, so i dont need to bring it in because of freezing or whatever. but since you mentioned that direct sun might not be the greatest, i moved it into the garage. ill try to get a pic for you. it was just another filter thing brs sells to aid in water reduction

 

[smitten with ocean life]

 

[UncommonSense]

Got it! So you’ve added a second RO membrane!

Okay, good info!

I see that your system doesn’t have a pressure gauge installed post-carbon, pre-RO membranes, this might make the next step a bit more of a runaround…

What I’m curious about is the home water pressure supplying this RODI system… dual membrane system don’t run nearly as efficiently when membrane inlet pressure is <65PSI! (The simplest way to test without a built-in RO system gauge is using a garden hose spigot pressure gauge from a hardware store!)

— This is the next question mark, Re; higher than expected post-RO membrane TDS readings!

 

[smitten with ocean life]

oh boy. i have no idea. even with all the filters changed the tds meter is still running at 5-9.

 

[UncommonSense]

oh boy. i have no idea. even with all the filters changed the tds meter is still running at 5-9.

Hmmm… okay! So, you should be getting somewhere in the realm of 3-5ppm TDS on the high end from your system in this configuration with 300ppm TDS tap water…

There’s room to optimize and get upwards of 3x the DI resin life, if you’d like!

To do this:

— Would you mind looking at the membrane flush valve (top of unit, behind white cartridges, on black waste line) to see if it has a number on it like “400” or “550”? — this pertains to your waste water flow restrictor’s total allowable liters per-day of flow, and should be changed when running dual RO membranes, like you are!

— knowing home water pressure via a hose spigot pressure gauge is another good metric to see if you’d benefit from a pressure booster pump on your system!

 

[smitten with ocean life]

hmm ok! ill check that out tomorrow. so youre saying that the reason to test the water pressure is to see if my system is efficient or not?

 

[UncommonSense]

hmm ok! ill check that out tomorrow.

Great!

so youre saying that the reason to test the water pressure is to see if my system is efficient or not?

Yes! If your home water pressure is >65-70PSI, you won’t need a booster pump to get your dual RO membrane filter system to run as intended! (Maximum RO membrane lifespan, minimum RO product water TDS!)

If your home water pressure is <65psi, your dual membrane system will not run as intended; (higher TDS product water, reduced membrane lifespan from working below designed operating pressure)


In addition, aforementioned waste water flush valve/flow restrictor combo dictates how much water gets thrown away via the waste line… — you do want discard a certain amount of waste water to keep the TDS of the RO product water very low! (not letting enough high TDS water out the waste line, [flow restrictor too small] will increase product water TDS, too!)

 

[smitten with ocean life]

ok. not sure i follow all that but ill try! lol

 

[UncommonSense]

ok. not sure i follow all that but ill try! lol

Don’t be afraid to ask if you need any clarification on anything, I’m here to help! — just eating dinner, finally! (Long day…)

 

[smitten with ocean life]

i truly do appreciate it. thank you! hope you can go put your feet up!

 

[smitten with ocean life]

ok @UncommonSense , the number is 550 on that connecter.

 

[UncommonSense]

ok @UncommonSense , the number is 550 on that connecter.

Okay, good! That’s an acceptable flow restrictor for dual RO membrane use! (The same size I use, in fact!)

So, the likely culprit of excess TDS is going to be water pressure then!

— Assuming you aren’t using the provided saddle valve that just stabs into a pipe; we can rule out tap water supply flow restriction…

— this said, it could be worth doing a cost-benefit analysis on adding an in-line pressure gauge post-carbon blocks, and a pressure booster pump! (Assuming say, 2X the resin life to be conservative; how long will it take for the upgrades to pay for themselves?)

 

[smitten with ocean life]

so youre talking like the booster pump kit for an ro system that brs sells?

 

[UncommonSense]

so youre talking like the booster pump kit for an ro system that brs sells?

I am!

— The Aquatech 8800 kit is correctly sized for your dual membrane RO system’s water production! (Mine lasted at least 7-8 years before starting to see appreciable pressure drop, and I can easily replace the pump head to make it like-new again!)

— The alternative is the Smart Buddy booster pump (200gpd+ model), which I’m not very familiar with… I believe it omits your automatic shutoff valve, actually!

— In addition to a booster pump, I highly recommend installing an in-line pressure gauge, like many RODI systems come with from the factory! — this is useful for system troubleshooting/maintenance, and is quite important when running a pressure booster pump to monitor pump performance, and adjust if over/under pressure!

https://www.bulkreefsupply.com/glycerin-filled-pressure-gauge-1-100-psi.html

 

[smitten with ocean life]

got it!

 

[smitten with ocean life]

wow. does it ever end? lol i always think i have to be about done spending money on this set up!

 

[UncommonSense]

wow. does it ever end? lol i always think i have to be about done spending money on this set up!

Hey, at least this upgrade will pay for itself over time!

Also, it means you’ll be producing RODI water around 40% faster! — 9-10gph is not unreasonable to expect!

 

[smitten with ocean life]

I DID IT!!! whohoo! just glued the last pipe together. now for a test run to see if i did it right! lol. its ok just to run plain old city water thru it for that right? ill pump it out when im done. just would feel better testing it out before i move it into the living room!

 

[UncommonSense]

I DID IT!!! whohoo! just glued the last pipe together. now for a test run to see if i did it right! lol. its ok just to run plain old city water thru it for that right? ill pump it out when im done. just would feel better testing it out before i move it into the living room!

Very nice work!!

I recall seeing at least one union with a missing seal o-ring in the initial plumbing photos… hopefully that was spotted and replaced?

Tap water is definitely the smart way to go for testing purposes! — just make sure it’s all leveled out before test filling; these bigger tanks hold nearly a ton of water!

Consider trying things like running the garden hose into the overflow box to fill it, hopefully showing any drain/bulkhead leaks before the entire tank is full of water! (Don’t ask me how I know!)