Does heat affect RODI water?

[Gtinnel]

Optimal membrane temps are 77F.
Most people do not reach this because of the cold water out of the pipe.

Dropbox

www.dropbox.com

In the winter my membrane works better. The 1/4" line flows over my wood stove in the basement warming the water.

Warm water does produce water quicker but the trade off is that the rejection rate goes down. I personally enjoy when it’s winter and my supply water is really cold because the tds after my membranes is usually zero before the di, but it does slow down and waste more water.

I believe membrane manufacturers use a warm water for their specs because it is a reasonable balance between condensate to permeate ratio and rejection rate.

 

[Buckeye Hydro Verified Sponsor]

Optimal membrane temps are 77F.
Most people do not reach this because of the cold water out of the pipe.

Dropbox

www.dropbox.com

In the winter my membrane works better. The 1/4" line flows over my wood stove in the basement warming the water.

Just to avoid any confusion, 77F is simply the water temperature at which the membrane manufacturers spec, or test their membranes. Akin to the 50 psi Filmtec (60+ psi for other manufacturers) uses to spec or test their membranes. Nothing says these are "optimal" or "ideal" or "best" temperatures or pressures.
Russ

 

[Dburr1014]

So testing the temps at the correct pressure for optimal performance are falsified?
I trying to understand what your saying.

 

[Randy Holmes-Farley Verified Community Expert]

So testing the temps at the correct pressure for optimal performance are falsified?
I trying to understand what your saying.

Im not sure what you are claiming is falsified.

77 is just a test temp, it is not being claimed as the best temp for any particular attribute that I can see.

 

[Dburr1014]

Im not sure what you are claiming is falsified.

77 is just a test temp, it is not being claimed as the best temp for any particular attribute that I can see.

I'm just looking at the performance testing that is here at face value. Maybe I'm reading into this to much?

And BTW, I'm not claiming any falsifications, I'm just asking what the numbers actually mean.

 

[KStatefan]

I'm just looking at the performance testing that is here at face value. Maybe I'm reading into this to much?

And BTW, I'm not claiming any falsifications, I'm just asking what the numbers actually mean.

It is just the performance of the membrane at those numbers. If you run at different numbers your performance will be affected per this table.

 

[CDubz]

I make my rodi water in my garage but it’s been so hot recently that it’s like 90-100 degrees in my garage. Could the heat affect my rodi water and rodi machine? Also i have rodi buddy in case that helps.

Two years south Florida garage system on well with no problems. Well water comes in 350TDS and comes out 4-6TDS. I store my RO water and DI water outside and it’s gotta be over 100F in there some days (I de-gas the CO2 to save resin overnight) I say leave it. Rather have a leak in the garage than inside.

 

[leo12345]

Others will chime in, but I know the ro membrane hates the heat and will come apart internally if its too hot.

Most membranes can withstand heat up to 113 degrees and that is the point where it damages the membrane. It sounds like you’re probably getting close to reaching that limit which would make me nervous, but if it’s already in the garage and hasn’t been damaged yet then it may be okay permanently.

On the positive side warm water going through your membrane will produce water quicker, but it also has a lower rejection rate and will allow more contaminated through the membrane depleting your di quicker.

I can't recommend anyone keep an RO system anywhere with high temps like posted in this thread. Temps >113F void the Filmtec warranty.

So even if the water were to get over 113 degrees would just the membrane break and all other cartridges like the DI, sediment, and carbon cartridge be fine or will they break as well?

 

[KStatefan]

So even if the water were to get over 113 degrees would just the membrane break and all other cartridges like the DI, sediment, and carbon cartridge be fine or will they break as well?

You would have to look at the specs for the filters and housings you are using.

 

[Buckeye Hydro Verified Sponsor]

You would have to look at the specs for the filters and housings you are using.

and the tubing, and the fittings, and....

 

[X-37B]

Here in Norcal its 100° for 3-4 months a year. Today 115°.
I have a 275g tote in the garage.
The water comming out of the hose will burn you in the summer.

So I turn the hose on flush out the hot water then hook it up to my unit.
Standard 5-10 minute flush before and after.
I would not run any water through my unit until the super hot has passed.
I have the same issue watering my garden.

 

[A_Blind_Reefer]

Here’s a screenshot of my mixing station temperature as it filled yesterday, and it’s not even August yet which is our hottest month. This is typical incoming cold water temperature during the summer here, day and night. The water company in our town gets its supply from a well, filter and treat, then they store it in huge above ground storage tanks. These tanks get blasted by the sun and while they are a couple miles from me, and the piping is underground, it’s still freakin hot when it comes out at my house. Unlike @90's reefer there is no amount of flushing I can do to get the temps down. I have the BRS seven stage rodi with an extra anion stage as I burn through that twice as fast as cation. I also have standard rodi tubing and fittings, nothing rated by NASA for life on Mars, just ordinary stuff. So, for about three months a year, for over four years now, I’ve had zero issues with my rodi. There are many others that have rodi here in the desert southwest under similar conditions. There’s nothing that can be done, other than only making rodi nine months a year or chilling the incoming water. I know it’s not ideal, it will void the warranty (although I don’t know how they would know, they don’t have tattletale devices like cell phones for water), it’s not recommended, and all that…. I’m just stating that it will probably work just fine if absolutely necessary.

Edit.. I forgot to mention that this is on day fifteen of temps over 110 degrees here

 

[X-37B]

Here’s a screenshot of my mixing station temperature as it filled yesterday, and it’s not even August yet which is our hottest month. This is typical incoming cold water temperature during the summer here, day and night. The water company in our town gets its supply from a well, filter and treat, then they store it in huge above ground storage tanks. These tanks get blasted by the sun and while they are a couple miles from me, and the piping is underground, it’s still freakin hot when it comes out at my house. Unlike @90's reefer there is no amount of flushing I can do to get the temps down. I have the BRS seven stage rodi with an extra anion stage as I burn through that twice as fast as cation. I also have standard rodi tubing and fittings, nothing rated by NASA for life on Mars, just ordinary stuff. So, for about three months a year, for over four years now, I’ve had zero issues with my rodi. There are many others that have rodi here in the desert southwest under similar conditions. There’s nothing that can be done, other than only making rodi nine months a year or chilling the incoming water. I know it’s not ideal, it will void the warranty (although I don’t know how they would know, they don’t have tattletale devices like cell phones for water), it’s not recommended, and all that…. I’m just stating that it will probably work just fine if absolutely necessary.

Edit.. I forgot to mention that this is on day fifteen of temps over 110 degrees here

Well thats a differnt situation. If you had the room you could do like you said and make and hold enough di water to get you through the summer.
Behond that I would just keep a few extra membranes around and call it good.

 

[leo12345]

Is there a way i can test my water to check if the water is filtering through the rodi unit right? Or would it be bad if I added some water conditioner to the water just to be on the safe side?

 

[twentyleagues]

You can get chlorine, phosphate,nitrate, ammonia tests, you can send it for an icp if you are really worried. It's probably fine but may set you at ease. I'm not a huge fan of using water conditioners. I've been told they don't harm the biological process but I have seen for example prime mess with a cycle. Used correctly Prime is a great product. When it first came out (I don't know if it was exactly when it first came out) we used it at an lfs I was helping at when bringing in a large fish orders. It worked great, a couple drops in the bag and then we could acclimate the fish that had just spent 24 or more hours in a bag in a box flying across the world. No losses to ammonia. We used it religiously, fish were much better off faster. They didn't really qt but new arrivals were not up for sale for a week after arriving and if a problem arose then they went in a treatment/qt area. But many times the owner would tell people to set up the tank add prime and start the cycle more often then not those people had constant issue with getting the tank cycled and maintaining a healthy tank on start up.
Just be careful with any water conditioners and I don't think you'll need it. Test if you are worried then if there is an issue you'll know and it can be addressed.

 

[n2585722]

I just had the RODI refilling the mix tank this morning and the tank temp is now 89.2. The garage was 92.4. I also checked the TDS meters when it was filling out of the RO filter it was 3 and 1. Out of the DI it was 0 on each. I have two meter systems. The one that came on the RODI system and one on my controller. The tap has a 259 reading and temp of 87 on the hand held meter. The DI out of the DI tank as it is refilling also is 0 and temp is 87. My guess is the tap water temp is 87 right now coming out of the tap. The RO membrane is the original and is over 8 years old. There is chloramines in our water and comes from a lake. I change the other filters on it once a year. I have a 42 gallon tank so I don't use as much water as someone with a larger tank. I would think that it has got up to near 110 in the garage during that time and as low as 37 degrees. I use a space heater in the winter to make sure it does not drop below freezing but normally it does not get that cold too many times in a year. The RODI is rated at 150gpd but I have not checked it since I have it automated and have only 20 gallon containers. The controller will alert me and shut off the RODI unit if it runs over 5 hours. The only time that has happened is when both the DI and mix tank refill at the same time. So so far I have had no issues with the RO membrane in garage temps in central Texas.

 

[Randy Holmes-Farley Verified Community Expert]

Is there a way i can test my water to check if the water is filtering through the rodi unit right? Or would it be bad if I added some water conditioner to the water just to be on the safe side?

If you monitor TDS, and it is 0-1 ppm then you are good to go.

If you have a reason to think chlorine or chloramine is getting through, a cheap chlorine kit will suffice.

 

[leo12345]

If you monitor TDS, and it is 0-1 ppm then you are good to go.

If you have a reason to think chlorine or chloramine is getting through, a cheap chlorine kit will suffice.

Will a cheap one from amazon do or does it have to be a special kind?

 

[Buckeye Hydro Verified Sponsor]

Unlike pH meters, a cheap TDS meter is fine. Here's the one you'd find in my toolbox:

TDS3 Handheld Meter

At Buckeye Hydro we specialize in providing the highest quality water filtration systems and accessories for every potential need.

www.buckeyehydro.com

People often find a meter with inline probes is more convenient (and therefore gets used more often). For a typical 4 stage RODI, you'd want a three probe meter. https://www.buckeyehydro.com/trm1-tri-inline-tds-meter/

 

[Randy Holmes-Farley Verified Community Expert]

Will a cheap one from amazon do or does it have to be a special kind?

If you mean chlorine kit, any one should be fine, but you might want to be sure it it intended for aquaria and not hot tubs where the needed range might be higher.