Moved RO/DI to the Basement...need advice.

[pdiehm]

So as the title says, i moved the unit inside to our basement. The issue was while in the garage, the waste line, which ran outside froze. The waste water backed up into the unit and absolutely murdered an entire canister of DI Resin in 13 or so gallons.

I tapped into the cold water line heading to the HW heater, and that's all good. The question I have is about the waste line...

I can go through the floor and tap into the kitchen sink drain, or run the line about 50-60' to the pipe where our sump pumps out air conditioning condensation. This goes right into the back yard.

Both options will be done with a saddle bracket. Looking to get this done sooner than later because I need to make some RO water.

appreciate all the info.

 

[saltwaterpicaso]

I would tap into the sink line that's what I did

 

[hawkinsrgk]

I would tap into the sink line that's what I did

+1. I did the same thing as well

 

[redfishbluefish]

I'd pick the shortest route....and that sounds like it's the sink.

 

[pdiehm]

Drilled it and went through other side. Trip to Lowes and $1.29 later here we go!

 

[pdiehm]

Plugged everything in. Opened the valve and then opened the RODI valve...making water at 50-53 psi.

Water also is not brutally cold either. Making bucket of RODI for my QT tank top off. Just tossed a thermometer in the bucket.

So far so good.

Water temp is 58. Looks like I will be running 50' of red tube through 85 degree water to raise the temps a little. New waste drain doing great. Cross em if you got em

 

[AZDesertRat]

Don't waste your time trying to heat the water, it is not feasable and requires more BTU's of energy than it is worth. Besides that colder water treats better so your DI will last longer if you don't try to warm it.

 

[pdiehm]

The good news is my TDS going into Di resin 1 is 3-5.

Even if I can raise it a little bit (ordered 75' of tubing) would be helpful. If I can get it into the 60's, my production should go way up. At least 10-11 minutes per gallon.

 

[AZDesertRat]

It is not helpful since it raises the TDS and shortens the DI life. It also requires tremendous amounts of electricity or gas to heat the water even a degree. Search BTU's and how much energy is required to raise one gallon of water only one degree, you will be very disappointed. Then there is the fact plastic tubing is a poor conductor of heat and cold so the heat exchange will be minimal. Trust me on this one, its not worth it. If you want to actually do something efficient buy an Aquatec 8800 booster pump which will overcome the low temerature and make your RO membrane even more efficient with minimal power consumption.

 

[mcarroll]

Don't waste your time trying to heat the water, it is not feasable and requires more BTU's of energy than it is worth. Besides that colder water treats better so your DI will last longer if you don't try to warm it.

It is not helpful since it raises the TDS and shortens the DI life. It also requires tremendous amounts of electricity or gas to heat the water even a degree. Search BTU's and how much energy is required to raise one gallon of water only one degree, you will be very disappointed. Then there is the fact plastic tubing is a poor conductor of heat and cold so the heat exchange will be minimal. Trust me on this one, its not worth it. If you want to actually do something efficient buy an Aquatec 8800 booster pump which will overcome the low temerature and make your RO membrane even more efficient with minimal power consumption.

+1

This is good advice - listen to the man!

Just keep your wasteroduct ratio correct and your system and water will be fine. (I have to dial down the waste line to match the product flow in the winter, then back up in summer.) If the makeup rate is too slow for your needs, then you either need a larger reservoir or the Aquatec pump AZ mentioned.

 

[pdiehm]

My pressure through the unit is fine at 50-54 psi. How will a booster pump increase how fast the unit makes water? specifically in the winter months when the water temp here is in the high 40's?

I'm not doubting, just trying to make sure I understand the why and how before I move forward with a pump like this.

 

[AZDesertRat]

By increasing pressure it forces the water through the membrane faster without compromising the quality. Two things have a major effect on a membrane, temperature and pressure. One or the other can compensate for the other but warmer water also has undesirable effects which is mainly increased TDS in the finished water. When you warm the water it becomes more viscous so passes theorugh the membrane easier, carrying some of the contaminants along with it. Colder water is more dense so does not pass through the membrane as easy so you make up for that with a booster pump.


Another perspective on Booster Pumps... - Reef Central Online Community

If we assume you have a 75 GPD Dow Filmtec RO membrane and your water pressure is 54 psi and temperature is 48 degrees you would expect to see 46 GPD. Increase that pressure up to 80 psi without changing the temperature and the GPD jumps to 71. Increase it to 90 and thats 81 GPD. Another added benefit is the membrane rejection rate goes up, it becomes more efficient at removing things so your RO only TDS goes down and your DI lasts longer.

Reverse Osmosis Drinking Water System | RODI Systems | Home Water Filtration System - Buckeye Hydro

On the flip side if you left the pressure at 54 psi and raised the temperature from 48 to 60 you would only jump from 46 GPD up to 59 GPD but your rejection rate will go down slightly so DI will not last as long and the real kicker is the amount of energy it would take to raise a bucket of water 12 degrees when you are circulating not only the treated water but also the waste stream through the bucket in the 1/4" plastic tubing. Add another 240 GPD to the 59 or say 300+/- gallons a day and a heater will not keep up or the hot water from your hot water heater would run constantly. It is hard to grasp until you study BTU's and how much it takes to heat or cool a gallon of water. This is science and not just an opinion or preference.

 

[pdiehm]

I really appreciate the information. That helps a lot.

From the sounds of it...I'm basically looking at 92 gallons per day out of my 150 gpd unit right now. Increasing the pressure up will probably take that 92 and make it 130-135 if I understand right.

Bulk Reef just told me my unit requires 65 psi. So a Booster probably needs to be ran all year long, but maybe turned down in the summer months.

Now, when the water warms up, I would want to stop using the booster pump right? High pressure, warmer water, would make it go through the membrane faster and easier right?

 

[AZDesertRat]

Yes raising the pressure will increase the GPD. I would watch the 150 GPD membrane very closely though, they are not very efficient as a whole and many vendors quit selling them. I had one 7 years ago and sold it as it did not meet my needs of 98% or higher rejection rate, Spectrapure discontinued them about that same time as they could no get enough of them to pass their quality control. I found a 75 GPD membrane and a booster pump set at 95-100 psi gave me the same amount of water and at 99.43% removal efficiency or rejection rate where that one was more like 96%. For every 2% you increase the rejection rate you double your DI life so that change alone more than doubled my DI life.

 

[pdiehm]

justed ordered the aquatec 8800 kit. should bump my PSI up to over 90 if I calculated right.

 

[pdiehm]

Found this on spectrapure's site:

http://spectrapure.com/manuals/CALC-FORMULA.pdf

Right now, my PSI is 53 or so. We'll use 53 for this example. My water temperature was 48 degrees.

53/60 = 0.88
150 (I have 2 75 gpd Membranes) x 0.88 = 132.5

Temperature Correction factor (website): 0.598
0.598 x 132.5 = 79 gallons per day currently (estimated...probably not far off).


Using a booster pump, if I am getting 90 psi, and from what I've read, that's probably what it'll be.

90/60 = 1.5
150 x 1.5 = 225 P.C.F.
225 x 0.598 = 134.55 gallons per day (roughly 5.6 gallons per hour).

Once the water starts warming up, I will probably need to adjust the booster pressure down to accomodate the warmer water so it doesn't go through the system as quickly.

 

[AZDesertRat]

If you are making water manually this is my preferred method of installing the Aquatec pump so it is protected from sediment:
http://spectrapure.com/huds/NEW-MO-BPK.pdf

There are other ways when you automate the system with things like the pressure switch, solenoid valve, ASOV and so on. Spectrapure has several additional diagrams in their Hook Up Diagrams section on these installations.

 

[AZDesertRat]

I run my booster between 95-100 psi year round. Our water believe it or not is around 58-64 degrees even in summer months in N Phoenix since the intake to the treatment plant nearest me is pretty deep in the lake.

What is your tap water TDS, RO only TDS and are you using softened water or have naturally soft water? What is your exact measured waste ratio using a measuring cup and clock or watch for exactly one minute from both the waste line and the treated line?

 

[pdiehm]

It was 2:1 waste:good when I set this up originally.

Tap water TDS isn't bad, 150 or so. Our water is straight flat, 7.0 pH.

I'll look into placing the pump before the membrane and after the first 3 stages. If i installed from the source, I have an easy place to install the pump at. I'll take a look at it tonight possibly.

 

[AZDesertRat]

Unless you have softened water I would not run your RO/DI at 2:1 waste ratio, the membranes will fail prematurely. Membranes must be flushed, there is no getting around it, and the best flushing is the continous flushing they get when in operation. This is especially true with a dual membrane system. BRS is full of BS when they mistakenly tell people dual membranes are a way of saving water. Remember, you are sending the concentrated waste from the first membrane ito the second so when you cut your waste to 2:1 it is much more concentrated going in and the membrane is going to fail quicker. If you have softened water and your 150 TDS you can probably cut it to 3:1 but I would never go any lower than that unless you plan on replacing membranes every 18 months or so. Others sell low waste systems but they also include two adjustable flow restrictors, hardness test strips and directions on how to test the TDS and hardness and how to trim or adjust the waste ratio to suit your exact water conditions. It is not a one size fits all 2:1 waste ratio if you expect to get the most out of your system.