RO/DI Hare Brain Idea

[RandyStacyE]

I would like to install my RO/DI unit beneath my kitchen sink to feed a faucet for drinking water (and my refrigerator water and ice maker) while at the same time feed a reservoir in my crawlspace about 30’-40’ away (directly beneath my new 75 gal tank with sump).

My thought is to install a 5 gal bladder tank (in the crawlspace) beneath the kitchen sink and split it off to a faucet and to the refrigerator using 3/8” OD hose.

I would also like to feed the reservoir (with a float valve) with the same 3/8” OD hose.

I’m thinking that using 3/8” OD hose will be good for running a good deal of volume to the faucet and also for effectively running a line approx 35’ away to the reservoir in the crawlspace.

My thought … is to feed a float valve in my sump from the underlying reservoir using an extra booster pump I have lying around and a pressure switch that came with it. Basically when the float valve drops then the booster pump will kick on to replenish this evaporation in the sump.

Here’s the basic plan:

[RandyStacyE]

I happen to have a few 55 gal plastic drums available to me, but they will NOT fit through the access-way into my crawlspace

I'm thinking that I will have to use a somewhat flimsy trash can for my reservoir … bummer.

I’m wondering if anyone has any advice or incite for this plan.

I’m thinking that a float valve in the sump ‘may’ be a bad idea as this ‘may’ trigger my pump 100s of times per day.

[MrRyanT]

I have a Tsunami AT1 ATO on my 110 display/55 sump. It has a high and low water point(preset) to turn the pump on/off. I have about 2 to 2 1/2 gals of top off per day and the pump only turns on for about 2 seconds about once per hour. Here's a link to it: http://www.aquacave.com/detail.aspx?ID=254 HTH

[djfrankie]

Looks good. How are u shutting the RO/DI off when not in use?

djfrankie

[MrRyanT]

Originally posted by djfrankie
Looks good. How are u shutting the RO/DI off when not in use?

djfrankie

I think the float valve in the water resevoir under the sump is shutting it off.

[RandyStacyE]

Yup, the reservoir should be full at all times due to the float valve and it is fed by the bladder tank.

I'm thinking that the 'weak link' is at the sump and it may be best to have a high point shut off and a low point triggering the booster pump.

[eznet2u]

There are several reasons I can see NOT to do this.

1. Bugs...Trashcan lids fit loose enough to allow entry.
2. TDS creep. You will be replacing cartridges every other month.
3. What happens if you have a leak? You'll never know until you get your water bill.

Other than those, it looks good.

[MrRyanT]

Originally posted by eznet2u
There are several reasons I can see NOT to do this.

1. Bugs...Trashcan lids fit loose enough to allow entry.
2. TDS creep. You will be replacing cartridges every other month.
3. What happens if you have a leak? You'll never know until you get your water bill.

Other than those, it looks good.

I pretty much agree except for #1. You can get some Rubbermaid containers with locking lids that would overcome that problem. I have one on my system like this that I just cut a small hole in to run my water line out. The power cord for the pump is just draped over the side and the top fits over it no problem.

[RandyStacyE]

I've been using the same trash can for at least 3 years and I have not had a single leak. I admit though ... I'd prefer to use one of my 55 gal drums, but they won't fit through my access hole in the crawlspace

I've never found a bug in the reservoir in the past ... though it was always kept in my garage. It does seal prety well so I'm not too concerned about that.

You are definitely correct about the TDS creep. There are ways around that one though I suppose. I suppose this could warrant float switches in the reservoir

This is getting too complex

[MrRyanT]

Originally posted by RandyStacyE
This is getting too complex

LOL........and I thought that only happened to me.

[kgross]

There are two changes I would suggest for you. First move the T to the garbage can closer to the RO unit before the T feeding the bladder tank/faucet. Then put a one way check valve after the first T. That way when you use up the water in your trash can, you can still get drinking water before the trash can files back up all of the way.

Kim

[djfrankie]

Originally posted by MrRyanT
I think the float valve in the water resevoir under the sump is shutting it off.

Umm, I maybe blind as a bat on this one. Would that only shutoff the product water and not your waste water so in essence your RO/DI system is still processing water.

I see you have the RO/DI filter directly connected to a main line.

Are u using an automatic water shutoff like the one above or something similar?



Image was borrowed from waterfilterguys.

djfrankie

[GrandeGixxer]

I also read somewhere on here recently and I don't know if it is true or not; you have to run a booster pump to get it to work for an icemaker.

[jmc74]

here is my .02 cents...

ok, you don't need the large tank, just run the line from the bladder tank to the float valve on the sump, as the evaporation is very slow, and the bladder tank should have about 12psi of air when empty, and should have no problem pushing water that far.

the problem I see on the booster pump, is that no float valve will overpower the 60psi the booster pump will provide, so you will have an overfilled sump.

and the auto shutoff valve should keep the system off, unless the pressure drops enough from the tank.

[jmc74]

you might also want to cosider a 14gal bladder tank, as the 5gal tank you have actually only stores about 2.5-3gal. and the 14g will have about 8.5-10gal

[jmc74]

better yet, get the 2nd tank and T-off the lines, and have a check valve between the small and large tank to prevent the large tank drainage from the fridge, so it will be exclusive use for the sump.

[kgross]

This drawing (post above this one) will drain both pressure tanks if the sump water needs more water than the pressure tanks hold. You need to put the check valve in between the drinking water side and the tank holding tank side. In this setup the only thing the check valve does is is keep the tanks pressure tank full if the drinking water tank is used. Where if the system goes into the fridge for an icemaker it is more important to keep water to the icemaker and for the wife to drink than it is to make sure the sump has water at all times. At the worst if the RO is dry your tank will only feed water as fast as it is produced, and the bladder tank will have to last until the sump is full, because you will not create enough pressure to fill the bladder tanks as long as the sump valve is open.

Kim

[jmc74]

Originally posted by kgross
This drawing (post above this one) will drain both pressure tanks if the sump water needs more water than the pressure tanks hold. You need to put the check valve in between the drinking water side and the tank holding tank side. In this setup the only thing the check valve does is is keep the tanks pressure tank full if the drinking water tank is used. Where if the system goes into the fridge for an icemaker it is more important to keep water to the icemaker and for the wife to drink than it is to make sure the sump has water at all times. At the worst if the RO is dry your tank will only feed water as fast as it is produced, and the bladder tank will have to last until the sump is full, because you will not create enough pressure to fill the bladder tanks as long as the sump valve is open.

Kim

on the contrary, you might want the large tank to be exclusive for the sump, as the line run is too long for the RO only, and the check valve will allow the tank to fill, but prevent it to supply water to the fridge, the small tank will supply water to the fridge/ice maker, as no person really needs 2.5gal at the time...

by having the large tank supply water to the sump only, even if your RO filters get plugged, you will have water to top off for few days. until you get new filters, as you will not see the lack of flow coming from the RO until is too late, this way the small tank will run out sooner and you will see when the filters needs replacing.

[jmc74]

hey one last thing, you don't want to drink DI water, you might want to run separate line to the tanks (if you get 2) run one from the RO and T off one line to the small tank and T off to the fridge, and the 2nd line from the T after the RO to the DI filter, and from the DI to the large bladder tank, install another T and run your line to and from the tank to the sump; and run also a check valve after the DI but before the T to prevent backflow to the DI media, your DI media will last longer,as you're not filtering drinking water only the top off water.

[manderx]

i don't like bladder tanks in general because they make the RO work against pressure, but you gotta do one if you want it to feed a drinking faucet/icemaker.

i'd put the bladder tank on it's own branch with a check valve to feed just the icemaker/faucet and never feed the reservoir. no need to make the bladder tank refill constantly as it would when feeding the topoff reservoir also. though if the bladder tank is empty from draining lots from the faucet at the same time you are refilling the reservoir, i have no idea what would happen to the icemaker if it wants water and doesn't get it (i'd bet it's engineered to be fine).

no reason the topoff reservoir needs to be more than a few gallons. also, you can put a solenoid/timer on it to only refill the topoff reservoir once or twice a day to eliminate tds creep.

i'd use a cheap ebay peristaltic instead of a booster pump to move water from the reservoir to the sump.

[jmc74]

Originally posted by manderx
i don't like bladder tanks in general because they make the RO work against pressure, but you gotta do one if you want it to feed a drinking faucet/icemaker.

i'd put the bladder tank on it's own branch with a check valve to feed just the icemaker/faucet and never feed the reservoir. no need to make the bladder tank refill constantly as it would when feeding the topoff reservoir also. though if the bladder tank is empty from draining lots from the faucet at the same time you are refilling the reservoir, i have no idea what would happen to the icemaker if it wants water and doesn't get it (i'd bet it's engineered to be fine).

no reason the topoff reservoir needs to be more than a few gallons. also, you can put a solenoid/timer on it to only refill the topoff reservoir once or twice a day to eliminate tds creep.

i'd use a cheap ebay peristaltic instead of a booster pump to move water from the reservoir to the sump.

listen; I work installing/servicing RO systems, and the TSD creep is the biggest bunch of CRAP I ever heard, is like the Magnets for your JOINTS to relieve pain. BS!

we use bladder tank all the time, and the RO last 3-5yrs w/o problems, as long as a autoshutoff valve is installed the RO pressure is only during filling, and we set our tanks empty @10-12psi of air.

most of our membranes are 80gpd RO TFT membranes and they remove 95-99% of TDS our standard is less than 010 TDS, and this is for drinking water! we also use OZONE in most of our systems too.

check our site
www.taylormadewater.com

[manderx]

and the TSD creep is the biggest bunch of CRAP I ever heard...

...and the RO last 3-5yrs w/o problems

tds creep has nothing to do with how long the membrane lasts. the ro relies on the pressure difference between the in and the out to compress the membrane to shrink the pores to get good clean water. when you turn a RO on and off, the first water to go through it gets through before it's fully pressurized and lots of solids get through. if you have a RO hooked up 24/7 to a float valve'd reservoir that feeds an autotopoff, it's going to turn on and off quite frequently to make only a few tablespoons or cups (depending on the footprint of the reservoir) of water at a time. this water will not be anywhere near as pure as water made once the RO has run for a while. it is documented in plenty of real articles, and you can even measure this yourself with a TDS meter. if you don't believe me, try it. make sure to read between the RO and the DI.

80gpd RO TFT

what's TFT? i've only heard of CTA and TFC. who makes it?

[kcress]

Hi RandyStacyE.

I think you're getting way too complicated.

I run what jmc74 has depicted with the exception of the multiple bladders. I also don't bother with the DI canister.

I run the bladder tank under my sink. I run 40 feet to my tanks. I recommend you run 3/8" for your domestic but don't run that to your tank. Run 1/4". A hundred feet of 1/4" will haul more water than your system can make anyway. I do batch make-ups every few days. I turn on a valve at the tank. This gets me 3 gallons delivered in about 15 minutes. A benefit of the 1/4" avoids the whole drinking water side problem. There is just enough back pressure so you can always still get water at the sink(at least a glassful usually much more).

You certainly need djfrankie's pictured automatic valve.

This then would ditch the whole holding tank, booster pump stuff.

Put the DI canister just between the bladder T and the tank. You sure don't want to drink DI water.

Your slow float dribbling make-up will assure that your bladder tank remains at least 80% full as the automatic RO valve kicks on after about a 1/4 of the bladder tank volume is used.

[RandyStacyE]

Originally posted by kcress
Hi RandyStacyE.

I think you're getting way too complicated.

I think you're right

I'll likely just ditch the the whole automated reservoir feeding the sump.

I'll just use an elivated 5-10 gal reservoir beside the tank inside of a cabinet or something. At least then I could just fill the reservoir once a week or so.

[AZDesertRat]

The first drawing is the way i would plumb it with the exception I would use float switches and a solenoid to combat TDS creep. Let the staorage barrel draw down several inches before starting the RO so you dilute the initial high TDS water.

I use a 14G pressure tank on my system (drinking, ice maker and DI usage) and still see the effects of TDS creep. My RO produces a TDS of 5.3 to 6.2 once it is running for a bit but the initial TDS may be much higher. My pressure tank climbs to between 14 and 25 after about two weeks so I make it a point to completely drain the pressure tank at least that often by making 25 gallons of RO/DI water in a single day to allow the tank to fill with freash low TDS water.