RO booster pump

[salty joe]

I just installed a 150 gpd RO membrane. I also installed a 1um sediment filer, new carbon and new DI resin. The pressure on the RO unit reads about 40 psi. The pressure on the house plumbing reads about 60 psi. At first I thought one gauge or the other is giving a false read. But there is quite a stream of waste which would surely drop the pressure. And just a trickle of purified water. I'd be surprised if I get 75 GPD.

Is a booster pump in order here? Would it improve the waste to purified water ratio? How do you hook up a booster pump to turn off when the RO system has no water running through it? Also, my water is cold. Don't know the temp, but if you leave your hands in it for more than 30 seconds it is painful. I have county water and the PH is between 7.5 and 8. I'm almost tempted to put the 35 gpd restricor back in.

[Eel Freak]

Well, maybe... The cold water certainly affects it... When I had my R/O unit before it was cold, I could fill a 5g bucket in under 20 minutes, now it takes closer to 45-50 because of the cold... I have a 75gpd membrane. I also run a booster pump (E-Chen something...) and my pressure resides between 80-94psi depending on water draw. I get a steady stream of pure water with this set up, and it has drastically reduced my waste-purified water ratio. I have the same set up as you, except with a 75gpd membrane...

With regard to auto shut-off, there are kits that you can get, however if I can make it to Lowes this week, I am going to try to DIY it using a 40-60 well pressure switch. I will post my results to this here and in the DIY forum...

Hope this helps!

[trb]

I recently put in a RO/DI system and my system gauge only read about 30 lbs and I was only getting a small amount of pure water, so I thought I needed a booster pump too. A friend asked if it had a valve on the waste water line. So I closed the valve about 1/3 and now, by restricting the waste line, it boosted my pressure up to about 60+. Now I get much closer to my rated 75 gpd, filling a 15g bucket in 5-6 hours.

As for the temp, I read about someone that ran like 100' or so of tubing in a bucket of water with a heater to raise the temp of their input water before the filter up several degrees to help with the water production.

Good luck!

[betoballer1]

I have to try that, I'm averaging around 30-40 pressure and I kno I should be around 60-70

[maynardjames]

will restricting waste water output effect or damage membrane or anything else. do you still get 0 tds after di

[Buckeye Hydro]

I just installed a 150 gpd RO membrane. I also installed a 1um sediment filer, new carbon and new DI resin. The pressure on the RO unit reads about 40 psi. The pressure on the house plumbing reads about 60 psi. At first I thought one gauge or the other is giving a false read. But there is quite a stream of waste which would surely drop the pressure. And just a trickle of purified water. I'd be surprised if I get 75 GPD.

This makes me wonder about your flow restrictor - what restrictor are you using?

How have you attached your feedwater tube to your home's plumbing?

Is a booster pump in order here? Would it improve the waste to purified water ratio? You bet.

How do you hook up a booster pump to turn off when the RO system has no water running through it?
You install a pressure switch - they are not expensive, and they plug right into the wiring for the aquatec booster pmup.

I'm almost tempted to put the 35 gpd restricor back in. Not a good idea with a 150 gpd membrane. You'll scale/foul the membrane and ruin it.

Russ

[Buckeye Hydro]

I recently put in a RO/DI system and my system gauge only read about 30 lbs and I was only getting a small amount of pure water, so I thought I needed a booster pump too. A friend asked if it had a valve on the waste water line. So I closed the valve about 1/3 and now, by restricting the waste line, it boosted my pressure up to about 60+. Now I get much closer to my rated 75 gpd, filling a 15g bucket in 5-6 hours.

What is yuour waste water to purified water ratio? You should restrict (usually with what's called a "flow restrictor") flow in the waste water tube so that you get about 4 parts waste water to 1 part purified water - regardless of the pressure.

If the pressure at that ratio if about 40 or less, go for the booster pump.

As for the temp, I read about someone that ran like 100' or so of tubing in a bucket of water with a heater to raise the temp of their input water before the filter up several degrees to help with the water production.
Anything over about 20 to 25 feet of 1/4" tubing will start to choke the pressure off. You'd be better off just to buy a $4 flow restrictor and have one for the winter and one for the summer.

Russ

[Buckeye Hydro]

will restricting waste water output effect or damage membrane or anything else. do you still get 0 tds after di

Don't go any lower than about 4 waste to 1 purified. If you do, your membrane will likely die a premature death.

Russ

[Rybren]

You'd be better off just to buy a $4 flow restrictor and have one for the winter and one for the summer.


Russ,

I'm in the same boat - cold water in the winter and my unit has a 5-ish to 1 ratio (on a 75gpd unit running at 55psi)

What restrictor would you use to boost production?

Thanks

[Buckeye Hydro]

You could drop down to a 50 gpd restrictor. Remember you can always trim the length of the capillary tube if you want the restrictor to allow more water to pass.

Russ

[Dalmerjd]

I have a pair of 90 GDP membranes and an Aquatec 8800 booster pump. My well pump delivers between 40 and 60 psi to the pump and the pump boosts it to 80 ish with a variable restrictor(valve) set to a 3:1 waste to good water ratio. I fill a 90 gallon aquarium is just under 12 hours. My feed water TDS is 350 ish and the TDS coming out of each membrane is 2-3ish. The feed water is warmed by my water reservoir to room temp. The level is controlled by a GHL level sensor and a solenoid valve driven by the P3 controller. I like the way it works.

I forgot to mention, with the valve on the waste stream I occasionally(once a week) open it wide open to help flush contaminates out.
My TDS is only 0 after the DI when it's fresh. All the other time it read 1. Once it hits 3-4 I swap it out. I go through about 100 gallons a week, water change and evaporation combined.
The DI lasts about 3-4 months(2 in series) and membranes about twice that long. The membranes are setup so the waste water from the first feeds the second.

[Rybren]

Remember you can always trim the length of the capillary tube if you want the restrictor to allow more water to pass

You've got me on that one. What's the capillary tube?

I find that it takes me a couple of hours to produce 5 gal of water (the source water is very cold) would dropping down to a 50 gpd restrictor speed things up as well? or Would a booster pump be a better choice (currently running at 55psi)?

Thanks

[salty joe]

This makes me wonder about your flow restrictor - what restrictor are you using?

This one.

http://www.tbaquatics.com/shop/150-gpd-flow-restrictor-420.html

It has no capillary tube. The 35 GPD restrictor has about 13" of capillary tube.



How have you attached your feedwater tube to your home's plumbing?

Temporarily, I have a garden hose adapter screwed into about 35' of garden hose which is connected to the cold water in my basement.

Would it be good practice to trim the capillary hose on the 35 gpd restrictor to 5"-6" for the winter and switch back to the other when it warms up?

Thanks,
Joe


Russ

[Buckeye Hydro]

Here's a picture of three typical capillary style flow restrictors:

http://i224.photobucket.com/albums/dd293/BuckeyeFS/HPIM0273.jpg

They consist of the plugs (the white, grren, or blue portions) and a skinny capillary tube. It is the length and inside diameter of the capillary tube that determines the amount of flow restriction.

Russ

[salty joe]

The flow restrictor I got does not have a capillary tube. Did I get a defective one?

[Buckeye Hydro]

Is yours a cartridge type - like this?
http://i224.photobucket.com/albums/dd293/BuckeyeFS/cartflowreswflushvalve.jpg

or maybe like one of these?
http://i224.photobucket.com/albums/dd293/BuckeyeFS/cartflowres.jpg

The amount of restriction provided by these types can't be adjusted.

You could always replace them with a capillary type

[Buckeye Hydro]

I'd get a 100 gpd restrictor and trim that a bit. Our 100 gpd restrictors have a tail on them about 4 inches long.

Russ

[salty joe]

Here's a picture of three typical capillary style flow restrictors:

http://i224.photobucket.com/albums/dd293/BuckeyeFS/HPIM0273.jpg

They consist of the plugs (the white, grren, or blue portions) and a skinny capillary tube. It is the length and inside diameter of the capillary tube that determines the amount of flow restriction.

Russ

My flow restrictor looks like one of these except it has no tail. It is light tan or white.

I just measured the purified to waste ratio-it is 10 to 1. Would it be a good idea to trim my 35 gpd restrictor with a 13" tail down to maybe 4"-5" and use it for the winter? I also have a shutoff valve for 1/4" line that I could put on the waste line to choke it until I got a 4 to 1 ratio. Does that make sense?

Am I correct to assume that warm water will yield a lower, better in my case, purified to waste ratio?

[Buckeye Hydro]

I'd get a 100 gpd restrictor and trim that a bit. Our 100 gpd restrictors have a tail on them about 4 inches long.

You might have luck using a ball vale on the waste line, but probably not. Ball valves are notoriously hard to use for fine adjustments.

Warmer water will yield less waste water.

Russ

[salty joe]

Thanks.

[trb]

What is yuour waste water to purified water ratio? You should restrict (usually with what's called a "flow restrictor") flow in the waste water tube so that you get about 4 parts waste water to 1 part purified water - regardless of the pressure.

If the pressure at that ratio if about 40 or less, go for the booster pump.



Thanks for the info Russ. I got the RO/DI from a friend that was upgrading to a 150 GPD unit, and didn't get any printed instructions on how to work it, so it was experimentation on my part. I haven't measured the output ratio, but I sure will if I can restrict the waste water line a bit more and get better results.

[salty joe]

My water temp is 42F. So the RO rejects a lot of water which drops the pressure giving me a 10 to 1 ratio. My water is much warmer in the summer. So I'm thinking maybe my best solution would be to get a 1/2" needle valve and plumb it into the waste line as a choke. Then every couple weeks or so adjust the choke for a 4-5 to 1 ratio. Or am I way off base?

[Buckeye Hydro]

An adjustable flow restrictor (i.e., a needle valve) is a decent way to go. We use these on higher capacity commercial systems. On those bigger systems you can use flow gauges to monitor the ratio of waste water to permeate. Unfortunately those flow gauges don't work on the size systems used most frequently in this hobby. So you are stuck measuring that ratio manually.

Joe - you have a 1/2" tube on your waste line? Those are typically 1/4"

Russ

[salty joe]

Thank you Russ. Cool! A solution with no moving parts.

Yes, my lines are 1/4". So I'll look for a 1/4" needle valve. Any suggestions?

I'm thinking of plumbing a couple Ts and shutoff valves to dump water into a fixed measuring cup and a measuring bowl. Then I could keep my eye on the water temp for choke adjustment.

Joe

[Buckeye Hydro]

I'll send you a PM re a needle valve. RC doesn't like commercial posts in the threads.

Russ

[NYDiesel]

Ive also noticed alot more waste water then clean water.can a supplied ball valve from my ro/di with a little flow restriction from the waste line help a little?

[RRaider]

I recently put in a RO/DI system and my system gauge only read about 30 lbs and I was only getting a small amount of pure water, so I thought I needed a booster pump too. A friend asked if it had a valve on the waste water line. So I closed the valve about 1/3 and now, by restricting the waste line, it boosted my pressure up to about 60+. Now I get much closer to my rated 75 gpd, filling a 15g bucket in 5-6 hours.

As for the temp, I read about someone that ran like 100' or so of tubing in a bucket of water with a heater to raise the temp of their input water before the filter up several degrees to help with the water production.

Good luck!

Is this on the waste line or is this the restrictor bypass for flushing the membrane? Give us a picture, i'll bet this is your flush valve.

[Buckeye Hydro]

Ive also noticed alot more waste water then clean water.can a supplied ball valve from my ro/di with a little flow restriction from the waste line help a little?

Sorry - I don't understand the question.

Russ

[salty joe]

I want to water my garden with the waste water which will make the waste line about 50'.
Do you think that will cause enough resistance to give a different waste/permeate ratio in the garden as compsred to right next to the RO unit?

[Buckeye Hydro]

Will there be any head pressure? Make sure you are not running the waste line up hill to your yard. You will probably be OK. Best to check it when you get it installed. You can always adjust your flow restrictor a bit to compensate.

Russ