Ideas for a RO/DI setup

[Jrk2195]

So I've never used a RO/DI unit before and I'm trying to figure out the best way to set it up. I live in Alaska (not my choice) so its freezing out 7-8 months of the year.

Would I be able to set up two 50 gallon tubs in my garage fill one up from the tap and heat the water in that tub and then my RO/DI unit syphon the water out of that tub into the other tub (the second tub would be my saltwater mixing tub). Or will I have to hook my hose up directly to the RO/DI unit and just let it slowly fill up the tote since the cold will affect the water production rate?

 

[NASAGeek]

RO/DI units work best with a PRESSURIZED input. Syphon is NOT going to be efficient at all. I use a SpectraPure 4 stage unit with a Pump to raise the pressure of the tap water.

Further, I use RO/DI for my ATO.... thus, I have it in my sump area. Yes, I use the same for water changes.... but in that case, I bring in jugs to collect the RO/DI.

Long answer short... I think you need at least tap pressure... and preferably a booster pump.

Hope that helps.
Mark

 

[billygoat2000]

So I've never used a RO/DI unit before and I'm trying to figure out the best way to set it up. I live in Alaska (not my choice) so its freezing out 7-8 months of the year.

Would I be able to set up two 50 gallon tubs in my garage fill one up from the tap and heat the water in that tub and then my RO/DI unit syphon the water out of that tub into the other tub (the second tub would be my saltwater mixing tub). Or will I have to hook my hose up directly to the RO/DI unit and just let it slowly fill up the tote since the cold will affect the water production rate?

You don't need a tub for the incoming tap water. just hook it into the water line at your house. Some people do use a setup like you described to get rid of excess co2 (they say it increases the life of the DI filter by having decreased co2 in the DI resin)... I doubt that is the case.

Regardless, just get the water from your water line. There are house connectors you can buy and also fittings that easily tie into your existing plumbing.

 

[Jrk2195]

You don't need a tub for the incoming tap water. just hook it into the water line at your house. Some people do use a setup like you described to get rid of excess co2 (they say it increases the life of the DI filter by having decreased co2 in the DI resin)... I doubt that is the case.

Regardless, just get the water from your water line. There are house connectors you can buy and also fittings that easily tie into your existing plumbing.

That's probably what I'm going to have to do but I'm wondering since it's so cold here in Alaska will the cold weather really have a MAJOR impact on the overall water i.e production, quality etc? Should I end up just getting a stronger RO/DI system that'll make a difference in the amount of water it makes?

 

[BiggieJohn]

If your cold water temp is under 50F (I'm sure it probably is) your idea of heating the water first would be a good idea. RO membranes are less efficient at colder input water temps.
You will need a pump to draw water out of the heating tank and push it thru the system. Get one that is designed for RODI systems, most suppliers have some sort of boost pump available for people with low water pressure. Ideally, you want 50-90PSI entering the RO membrane, after the sediment and carbon filters.

 

[Jrk2195]

If your cold water temp is under 50F (I'm sure it probably is) your idea of heating the water first would be a good idea. RO membranes are less efficient at colder input water temps.
You will need a pump to draw water out of the heating tank and push it thru the system. Get one that is designed for RODI systems, most suppliers have some sort of boost pump available for people with low water pressure. Ideally, you want 50-90PSI entering the RO membrane, after the sediment and carbon filters.

Is there any harm if I decide to just run it from my tap anyways other than it being slow? I'll only need to be producing 30-40 gallons in a two week time period. (it would speed up through summer)

 

[89Foxbody]

I have the BRS 5-stage which is overkill for me because my well water is under 10 TDS...but I used to live in an apartment with chloramines in the water so that's why I have it. I tapped into a water line in my basement and the output goes outside into my rain barrel. Then I have two brute cans for RO water and new salt water.

 

[neiltus]

I am sure a 150GPD dual membrane hooked up to an adequate pressured supply would work fine.

Or is your garage below freezing?

 

[Jrk2195]

I am sure a 150GPD dual membrane hooked up to an adequate pressured supply would work fine.

Or is your garage below freezing?

My garage itself will stay around 68-75 degrees while its -10 outside. It's well enough heated so the RO/DI unit itself won't be in the cold just the water that'll be going to it.

 

[BiggieJohn]

Is there any harm if I decide to just run it from my tap anyways other than it being slow? I'll only need to be producing 30-40 gallons in a two week time period. (it would speed up through summer)

I found this table. Might help explain the reduced output at lower temps.
https://www.apswater.com/page59.html

As the table shows, at near freezing temps, you will get less then 1/3 the rated output of 75 Galons/day

 

[BiggieJohn]

My garage itself will stay around 68-75 degrees while its -10 outside. It's well enough heated so the RO/DI unit itself won't be in the cold just the water that'll be going to it.

You could probably get away with using a long loop of tubing before the input to the RO/DI unit. 20-30ft, coiled up, in a heated garage should help raise the temp enough. Check the water temp at the faucet you are going to use, if the pipes are in the heated part of the house/garage your water temp might not be too bad. Remember that all RO membranes are rated at 77F and 60PSI

 

[Jrk2195]

You could probably get away with using a long loop of tubing before the input to the RO/DI unit. 20-30ft, coiled up, in a heated garage should help raise the temp enough. Check the water temp at the faucet you are going to use, if the pipes are in the heated part of the house/garage your water temp might not be too bad. Remember that all RO membranes are rated at 77F and 60PSI

Looks like I will be proceeding with the build then. That was the only issue I was mainly coming to was figuring out how that was going to work. I'll probably be posting pictures if not more questions to make my first saltwater tank perfect