Some (simple) RO/Di questions

[OzoneParkGuy]

Only problem i see is that you have no flow restrictor... a flow restrictor is used in conjunction with the membrane to produce the reverse osmosis.

 

[E.intheC]

well.. after a very crazy (and enjoyable) weekend, I decided to take a stab at the RO/Di conundrum.

I put the filters in the correct spots and had the tubing go in the right direction.. Now it fills from the left to the right.

Here's the question.... no water is coming out of the Di canister AT ALL.. only waste water coming out of the RO membrane's line.

What the hell could be causing this? I checked and all the connections are spot on, and there doesn't appear to be an obstruction of any sort.. I'm stumped.

 

[KathyC]

well.. after a very crazy (and enjoyable) weekend, I decided to take a stab at the RO/Di conundrum.

I put the filters in the correct spots and had the tubing go in the right direction.. Now it fills from the left to the right.

Here's the question.... no water is coming out of the Di canister AT ALL.. only waste water coming out of the RO membrane's line.

What the hell could be causing this? I checked and all the connections are spot on, and there doesn't appear to be an obstruction of any sort.. I'm stumped.

Poor Eric...

Did you install the filters right side up? (yes, it matters, that's why some come with arrows on them)
How long has it been running?
Do you have the water turned up all the way?

Got a pic?

 

[E.intheC]

Hmm.. (I think) I installed the filters the right way, but I'll check.

It was running for about 15 minutes, then I stopped the water to check and see if there were obstructions, and reconnected everything and ran it again for another 10 minutes. Not a single drop.

The water was turned up almost all the way.

No pictures :lol2:

Thanks for the help Kathy! Let's see how complicated I can make this

And as a side note: this is why you read and know EVERYTHING about the new project that you're starting BEFORE you start messing with it, lol

 

[KathyC]

The water was turned up almost all the way.

No pictures :lol2:

Thanks for the help Kathy! Let's see how complicated I can make this

And as a side note: this is why you read and know EVERYTHING about the new project that you're starting BEFORE you start messing with it, lol

'Almost' only counts in hand grendades, horse-shoes & nuclear weapons...CRANK IT ALL THE WAY UP!!!

Awww, come on, I wanted to see if you got your toes in more pics!

If the membrane is new - it takes a bit of time to start going..will see if I can find some specific info on that for ya...

 

[E.intheC]

'Almost' only counts in hand grendades, horse-shoes & nuclear weapons...CRANK IT ALL THE WAY UP!!!

Awww, come on, I wanted to see if you got your toes in more pics!

If the membrane is new - it takes a bit of time to start going..will see if I can find spme specific info on that for ya...

...LOL to a few comments above. (and no, I won't be getting more pics with my toes in them..lol)

Thanks for the help

 

[KathyC]

read here
http://www.airwaterice.com/category/z.91/

Try the suggestions mentioned

 

[E.intheC]

Thanks Kathy. I just read that briefly. Hopefully it's not the membrane.

Side note; the RO/DI is working OK right now, but not great. Looks like it's producing at a rate of 10 gallons ++ of waste water to every gallon of RO... awesome ...but it's better than nothing I guess

EDIT.. I went back and read more.. what is the ASOV?

 

[E.intheC]

oh... to add. I took 2-5 gallon buckets. One for the waste water and one for the RO water. (Not even DI yet..)

For 1/4 gallon of RO water, the unit produced 2.5 gallons of waste. (D'oh!)

 

[KathyC]

Yes, it is painful to see how much waste they produce

The answer to your other question
http://www.airwaterice.com/category/z.7/

 

[E.intheC]

Yes, it is painful to see how much waste they produce

The answer to your other question
http://www.airwaterice.com/category/z.7/

Quoted for truth.

Looks like I have some more reading to do.
Thanks again for the links.

 

[masterswimmer]

Eric,
Here's my take on this.......

1 - what is your incoming source water PSI? This sounds like it could be the root of all your problems. Low PSI will not be able to 'push' water through the RO Membrane. It'll all run to waste water.

2 - ASOV = Automatic Shut Off Valve

LMK if I can help. I'm taking a preliminary stab at the resolution to your woes and guessing you're going to need a Booster Pump.

Russ

 

[E.intheC]

Thanks Russ. I have to check the PSI.. I'll look up the best way to do that this evening. Do most people run an ASOV? I have a check valve of sorts on the incoming water (I realize this is different than the ASOV) but not the ASOV.

 

[masterswimmer]

Thanks Russ. I have to check the PSI.. I'll look up the best way to do that this evening. Do most people run an ASOV? I have a check valve of sorts on the incoming water (I realize this is different than the ASOV) but not the ASOV.

You're welcome Eric.

A check valve only prevents water (or liquid) from reversing the flow through tubing/pipe. It won't shut it off from flowing in its intended direction.

Water Pressure Gauge

Russ

 

[OceanBlue2]

I would remove the flow restrictor and use a shut off valve in the waste line. Close the valve slowly until the RO unit produces RO water and waste water at a ratio of 1 to 4. Do not close the valve completely or you might risk damage the membrane. A RO unit with an effecitve flow restrictor should has an approximate ratio of waste/product about 4:1 to 3.5:1 and flow rate of 150 to 1200 ml per minute depends on the size of the membrane.

IMO, the waste/product ratio is more important than the flow rate because a flow restrictor usually allows too water pass through and drop the water pressure too much to make the membrane ineffeciency.

 

[KathyC]

I just want to mention that the water pressure in Nassau lately has been awful - they put a ban on watering lawns/car washing in place last week due to the lack of water/pressure here.

Even in a private home I am struggling to make rodi water most days and I have all new filters & membrane in my unit. Other days it works like it usually does at 4/1 and I can fill my Brute can overnight.

Eric - are you in a private home?

 

[E.intheC]

Thanks again for the help guys.

In the meantime, short term.. can I use the restrictor valve on the waste side (remove it from its current location) or is that a bad idea?

I'll have to order an Automatic Shutoff though

 

[E.intheC]

I just want to mention that the water pressure in Nassau lately has been awful - they put a ban on watering lawns/car washing in place last week due to the lack of water/pressure here.

Even in a private home I am struggling to make rodi water most days and I have all new filters & membrane in my unit. Other days it works like it usually does at 4/1 and I can fill my Brute can overnight.

Eric - are you in a private home?

Kathy, I'm in an apartment complex.. (although I wish I had a private home )

 

[E.intheC]

one more quick (stupid?) question.. ...can the RO system pump out water TOO fast? I reconnected everything tonight... and the water is coming out of the RO line at about 4 gallons per hour (maybe a bit faster).. I think it's a 75 gallon per day unit.

I know it's not the waste line.

 

[masterswimmer]

one more quick (stupid?) question.. ...can the RO system pump out water TOO fast? I reconnected everything tonight... and the water is coming out of the RO line at about 4 gallons per hour (maybe a bit faster).. I think it's a 75 gallon per day unit.

I know it's not the waste line.

If your system is a 100 gpd unit then 4 gph is spot on mate.

There are three variables that contribute to the output of an RO/DI system. The membrane is the key factor to the output. The membrane is subject to variations in water quality, water pressure and water temperature. Most membranes are set at 50 psi and 77 degrees F.

Lets remove the water quality factor because there is no way for you to adjust it.

As the water temperature drops below 77 F the less output you will get.
As the water pressure drops below 50 psi the less output you will get.

The reverse is true as well. As temp and/or psi rises above the baseline stated above, the output will increase too. I'm not schooled well enough to give you an exact calculation of the expected output based on these variables, but this is in fact true. Therefore, you can reduce the output to the expected 75 gpd by lowering the water pressure and/or water temp. I would leave the temp alone at whatever your cold water produces (never turning on hot water supplied to your RO/DI) and only adjust the water pressure.

I know this was somewhat vague and a bit ambiguous, but I hope the theory helps.

Russ