Good to know. Thanks for the information. I actually did it just now the other way but I run the risk of losing the small collar pieces in the nut of the float valve. I have an extra ball valve from the media reactor I got. I'll give that a shot. Side note. When my float was activated and the preassure just built up on the auto **** off of the RODI. My DI cartridge just leaked all over the place. It felt real right. Not sure what happened. Try again next time.
RO/DI Question - RO Membranes in Series
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Put a very thin coating of edible foodgrade silicone grease or in a pinch vaseline on the O ring of the DI canister and screw it on hand tight with no more than 1/8 turn more with the wrench, they don't have to be real tight, the O ring does the sealing.
coralcrazy
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Update here.
I hooked up the pressure gauge just before the membrane. I am currently getting 56psi. I tested the water coming out of the RO before the DI and I am getting about 40 tds which means the DI is working overtime. I contacted someone at Bulk Reef Supply and they told me this was normal.
Does this sound right, anything else I can do to lower the tds coming out of the membrane?
I hooked up the pressure gauge just before the membrane. I am currently getting 56psi. I tested the water coming out of the RO before the DI and I am getting about 40 tds which means the DI is working overtime. I contacted someone at Bulk Reef Supply and they told me this was normal.
Does this sound right, anything else I can do to lower the tds coming out of the membrane?
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Chad those numbers could be accurate at the pressure you have. Your in need of a booster pump. Somewhere between 80 and100psi you should get a 99% rejection rate. Don't worry about the pressure. Filmtec and most membranes handle 150psi. Aquafx has a great deal on a booster pump, it is adjustable pressure too.
coralcrazy
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Hey question. I show only 44 psi on my BRS 75 per day plus system. And I get a 0 reading. Should I be worried about the psi being low? At first I was ready to get a booster. But after using it 2- 3 times it seemed to produce water faster. Should I still consider a booster? And will the aquafx fit on a BRS model RODI?
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I also just realized that your unit is new. You definitely need a booster pump. It will be cheaper in the long run than buying DI resin. Here is a pic of my setup
coralcrazy
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I think it depends on tds going in. I'm in so cal and my tds in is really high 450-500. If your is lower the membrane doesn't need much pressure.
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Derek's most likely your water going in doesn't have a lot of TDS so you are not noticing or you are not measuring yourTDS post membrane pre DI. If you have DI than you should always get zero unless it has exhausted. A booster pump will also improve your output gpd and increase the rejection rate. And yes the aquafx pump works perfectly with my BRS 6stage. You can see it in the photo above
Where are you getting your tds reading pre or post DI.
Where are you getting your tds reading pre or post DI.
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I show you how well good psi input can affect rejection rate.
I currently have saltwater intrusion into my well down in Florida where I live. My tds going in is around 1770 yes that hi.
I currently run pressure throughout the RO and reaches the membrane at 100 to 110 psi.
Post membrane tds is from 32 to 26 that my friends is a high rejection rate.
If you have tds input around 500 than there is no reason you can't get down to 2 or 3 tds post membrane or lower with a booster pump like I did when I had city water.
With low tds post membrane your DI resin will seem to last forever.
My issue with saltwater intrusion is going to be a thing of the past this month. I'm installing a whole home RO system with a few extras to my well system. I then will have tds in the teens at every faucet. Imagine what my RO system will do with those low tds. I will still run booster and DI my water will be so pure and the DI will seem to last forever.
If your final product has any tds reading then don't use it in your tank. Replace DI resin and make more water.
I currently have saltwater intrusion into my well down in Florida where I live. My tds going in is around 1770 yes that hi.
I currently run pressure throughout the RO and reaches the membrane at 100 to 110 psi.
Post membrane tds is from 32 to 26 that my friends is a high rejection rate.
If you have tds input around 500 than there is no reason you can't get down to 2 or 3 tds post membrane or lower with a booster pump like I did when I had city water.
With low tds post membrane your DI resin will seem to last forever.
My issue with saltwater intrusion is going to be a thing of the past this month. I'm installing a whole home RO system with a few extras to my well system. I then will have tds in the teens at every faucet. Imagine what my RO system will do with those low tds. I will still run booster and DI my water will be so pure and the DI will seem to last forever.
If your final product has any tds reading then don't use it in your tank. Replace DI resin and make more water.
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Chad it will work but I like the booster pump kit from aqua fx because they have great service and there pump most importantly is psi adjustable. The link you put up is only 80 psi and not adjustable. And it is rated 80 psi only for membranes rated at 85 to 100gpd to achieve that rating.
Do yourself a favor buy the aqua fx pump kit. If you don't like it return it.
I use it with a 75 gpd filmtec membrane and it produces plenty of water.
Do yourself a favor buy the aqua fx pump kit. If you don't like it return it.
I use it with a 75 gpd filmtec membrane and it produces plenty of water.
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Thanks for the advice, I'll make my purchase now.
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Pete over at fx is great to talk to if you call. Also they are very knowledgable.
I'm just a happy customer and received great service from them.
I'm just a happy customer and received great service from them.
Chad 56 psi if fine for a RO membrane and a booster pump is not needed, 40 psi is the minimum and Dow rates their membranes at 50 psi. 50-60 is about average.
The 40 TDS after the membrane is a concern though but a booster pump will not magically cure your problem. Its not pressure related if you have 56 psi at the tap.
If you have an inline pressure gauge you can more around, test the pressure on the incoming side before the sediment filter with the system in operation, then test it again between the carbon block and the RO membrane again while in operation to check if your filters are plugged or fouled.
Also check your tap water TDS, your RO only TDS before the DI and your final RO/DI TDS.
Next test you water temperature and measure you exact waste ratio using a measuring cup and clock or watch for exactly one minute from the waste line then from the treated line.
Raising the pressure with a booset pump from say 40 psi up to 80 psi will gain you about 1% rejection rate so is beneficial but maybe not cost effective. You need to find your membrane problem before investing a lot of money in something you amy not need. Get the numbers above and lets do some more troubleshooting first.
If you do choose to invest in a booster pump make sure it is a genuinbe Aquatec 8800 and not an off brand or clone. Aquatec is the standard of the industry for a reason and they hold up to decades of use.
The 40 TDS after the membrane is a concern though but a booster pump will not magically cure your problem. Its not pressure related if you have 56 psi at the tap.
If you have an inline pressure gauge you can more around, test the pressure on the incoming side before the sediment filter with the system in operation, then test it again between the carbon block and the RO membrane again while in operation to check if your filters are plugged or fouled.
Also check your tap water TDS, your RO only TDS before the DI and your final RO/DI TDS.
Next test you water temperature and measure you exact waste ratio using a measuring cup and clock or watch for exactly one minute from the waste line then from the treated line.
Raising the pressure with a booset pump from say 40 psi up to 80 psi will gain you about 1% rejection rate so is beneficial but maybe not cost effective. You need to find your membrane problem before investing a lot of money in something you amy not need. Get the numbers above and lets do some more troubleshooting first.
If you do choose to invest in a booster pump make sure it is a genuinbe Aquatec 8800 and not an off brand or clone. Aquatec is the standard of the industry for a reason and they hold up to decades of use.
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coralcrazy
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PSI Measurments:
70 PSI coming into house
60 PSI coming into sediment block
56 PSI just before the membrane (inline)
TDS Measurment:
450 to 500 going into RO
35 to 40 after membrane
0-4 after DI depending on exhausted resin
Tempeture of water ranges from 60 to 75 (located in garage)
Waste water ration not measure yet. I have a storage tank connected and that will take some time to rig up.
You should not have a 10 psi drop between the outside tap and your sediment filter unless you have a pressure regulator somewhere. RO membranes flow at only a quart or so a minute so its not friction loss due to high velocity. 4 psi is also a pretty good drop between the inlet and the RO membrane, I rarely see 1-2 psi drop with clean filters and change mine out at 2-3 psi.
I suspect you have either a clogged membrane, a membrane that is not seated correctly inside the housing or a cracked RO housing allowing water to bypass the membrane.
Measure the wste ratio and tell us the m/L or ounces for each in one minute, this may also tell us if you are bypassing the membrane since we can easily calculate the flow at 56 psi and water temperature with a good membrane.
I suspect you have either a clogged membrane, a membrane that is not seated correctly inside the housing or a cracked RO housing allowing water to bypass the membrane.
Measure the wste ratio and tell us the m/L or ounces for each in one minute, this may also tell us if you are bypassing the membrane since we can easily calculate the flow at 56 psi and water temperature with a good membrane.
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coralcrazy
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I do have a pressure regulator on my house and the RO unit is located about 10 feet away from it.
My unit is only about a month old. I'll try to get a measurement tonight when I get home.
Thanks for you help.
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56 psi sucks yes Dow filmtec is rated 50 psi for a 95% rejection rate 60 psi for a 98% rejection rate. Filmtec is rated to 150psi max. Most of us would prefer the highest rejection rate. With the cost of DI resign the lifespan and cost of pump would be out weighed.
I get very high rejection rate running 100psi at membrane and 60psi flushes. How high of a flush psi do you get with a 56psi input. Flush it and watch the needle drop. Although to much pressure is not good to flush your membrane but Low pressure doesn't get the job done. Not everyone has a computer controlled RO setup either. We are talking about a BRS setup which I also own.
I get very high rejection rate running 100psi at membrane and 60psi flushes. How high of a flush psi do you get with a 56psi input. Flush it and watch the needle drop. Although to much pressure is not good to flush your membrane but Low pressure doesn't get the job done. Not everyone has a computer controlled RO setup either. We are talking about a BRS setup which I also own.
