NYC water ruining RODI systems?

[rbcjoker]

Hey folks, I don't post much here, but I've run across a problem that might be particular to our area.

I bought my first RODI system in early February, and while slow, it was working ok at first. I only use it every other week, for just 6 gallons (I have a small tank.) Now, water production has slowed to a dead crawl. It took me 7 hours last Saturday to get half a gallon of water. I called the manufacturer, and they said they have seen an increase in the last two months of complaints from the five burroughs. They suspect that the water is being treated with a coagulant, possibly alum, and that would clog up a RODI system. Is anyone else having this problem, and if so, how are you solving it?

 

[rich]

Yes. I have a 4 system unit. I change the first two filters once a month. Seems to do the trick.

 

[rbcjoker]

Yes. I have a 4 system unit. I change the first two filters once a month. Seems to do the trick.

How often are you running yours, and for how long?

 

[rich]

I run it once a week for 10 gallons. I dont have a big system.
I use http://www.marinedepot.com/Aquatic_..._DI_System-AquaticLife-AK01371-FIRORD-vi.html

 

[rbcjoker]

I have a small unit, too, a RO Buddie from that same company. They offered to send me new cartridges, so hopefully that will work.

 

[vio]

NYC , have a good water ,Manhattan less than 50 TDS, i have friends NJ,PA got over 200 TDS,
Take out first 2 filters, run and see if is any restriction.

 

[theMeat]

Obviously 200 tds is more than 50, but 50 could be worse, and harder on ro/di unit depending on what those contaminants are, or if they're small enough to make it through your filters. If you have a 5 micron, and the particles are smaller, then most get through, your membrane gets clogged, and resin quickly depleted. Use a micron that's much smaller than the particles going through it, and the filter clogs right quick. It's best to experiment with dif size micron filters to determine what size particles you're dealing with in your supply. I run a five, followed by a one, and they last 6+ months. If The first filter was a 1 micron, then it wouldn't last a month. A friend of mine further east uses a 10, and that's all he needs. We know this because we ran a 5 after the 10 and the 5 stayed clean.

Partial filter, no matter the size, do nothing for chlorine, chloride, fluoride, etc. Then if you don't have enough carbon block, or exhausted carbon, your membrane gets burned, and production falls off. If you're on well water or a supply that doesn't have these type of things than you don't need to run a carbon block.

If you're on the 4 floor or whatever in queens, then it's possible your pressure is too low for the gpd you're trying to make. The more gpd your membrane, the more important water pressure is to longevity for the unit. Might be enough when all the partial filters are new, but once they start to clog the pressure to the membrane drops and so does production.
You can also play around with the size of the flow restritor, depending on pressure, and gpd in your membrane. You want at least 4 to 1 waste/ product.

 

[Reef Trends]

A booster pump would certainly help and is also better for the filters lifespan.

 

[theMeat]

A booster pump only helps when there's not enough pressure. The more gpd your membrane, the more pressure you need. If you're reading 50 psi at tap to ro unit, a booster will do lil to not up to around 100 gpd. If you're at 40-45 psi, you should prolly stay under 75 gpd, or get a booster pump.

 

[nano]

NYC is apparently known for having a lot of sediment in the water in spite of a relatively low TDS reading. I replaced my standard sediment filter with a spectrapure 0.2 micron filter. They are back-flushable, so you can restore the flow a little bit when they clog up, but I still had to replace it after a year of about 7-10 gallons per week. The carbon block will also clog with particles, so you will probably need to replace that along with the sediment filter.

Once the sediment and carbon filter get clogged, they reduce the pressure at the RO membrane, and it will simply stop working when pressure drops below a certain threshold. A booster pump would help that to a certain extent depending on your building water pressure.

Before this, I had an RO buddy. It was very slow to begin with (about 2 hours per gallon), because my building pressure is very low. That sediment filter clogged after about 200 gallons.

 

[vio]

for me is easy, i got 72 psi after 4 huge building filters (20 micro) i use 1 micro filters , my pump push 80 psi, i got zero TDI before and after membrane (2) the blue tank is DI. I run back flush also Not to mention 20" filters.

 

[FelisMaximus]

I had the same problem with 2 different Aquatic Life systems and came up with a very unlikely solution. It seems that their RO/DI units have a real problem with cold water, but for some reason work great with hot water (I kid you not). Hook it up to your hot water line, run it for 10 minutes and the flow will be restored to normal. Cold water still won't work, though.

P.S. Never going to purchase another AL unit ever again. Going to install a BRS system when I start setting up my new tank.

 

[Wondering]

Have you checked the tds levels after running hot water in your rodi unit? Reason im asking is that hot water will ruin the membrane.

 

[ecvernon]

Its not the water it is the RO Buddy. It did the same thing to me. The sediment filter clogs extremely fast and slows production to a crawl even with a booster pump. I changes to and old BRS unit i had laying around and problem solved.

 

[ecvernon]

OP I have an aquatec 6800 if you want to try and see if helps your situation. Im in 11691

 

[edd]

I had the same problem with 2 different Aquatic Life systems and came up with a very unlikely solution. It seems that their RO/DI units have a real problem with cold water, but for some reason work great with hot water (I kid you not). Hook it up to your hot water line, run it for 10 minutes and the flow will be restored to normal. Cold water still won't work, though.

P.S. Never going to purchase another AL unit ever again. Going to install a BRS system when I start setting up my new tank.

water below 65deg slows production, the colder the slower. and hot water can damage your membrane.
i put a washing machine y hose on mine so i can adjust the temp.
i also read that hot water will exhaust your DI faster.

 

[FelisMaximus]

I test the water every time and so far - so good. Once the TDS reading starts to creep up I'll figure out if its worth the money to purchase new filters for the unit. Regardless, I'll be switching to a BRS system in the near future. Now, if I can only finally decide between 80, 120 and 125

 

[Wondering]

Go with 120. Light coverage is the "cheapest" with 120

 

[johnsonpics]

Hey Everyone,
I actually live near Rich in Chelsea, NYC and I have to say I've had to change my sediment and carbon filters Waaaay sooner than normal, by like 6 months! It's not a booster pump issue, it's not an "are you sure your doing it right" issue. I don't know what, but the water has been weird for the last few months.

 

[fritz]

Strange, I live in Southern Brooklyn (Marine Park) and I've noticed nothing out of the ordinary. I make up roughly 45 gallons of RODI a week and both production and filter lifespan has been the same as it has for the last year or so. We are all using the same feed water, perhaps it something much more local or as was mentioned something with the brand of filter being used.

I'm using the BRS and I get about 50 PSI to the membrane. My feed water is usually around 9 TDS and is 0 on the output. This has been true for more than the last decade. You city guys might be getting water through some really nasty pipes which could be causing some of your issues.