The importance of RO/DI water

[Jaybird]

Here's a little experience I had yesterday that may give some people who are on the fence about RO/DI units a little bit of a push.

I bought a 50 gallon-per-day unit and have had it attached to the sink in the back hall for about two months. Needless to say, my wife wasn't too happy about always having it there.

Yesterday I moved it to the garage and attached it to the wall near the door to the back hallway. The connection goes to the faucet in the garage.

My DI resin was about 20% orange when I hooked it up. I had topped up the tank with about 4 liters of RO/DI water and went to fill up the bottles I used. After four liters of RO/DI water from the tap in the garage my DI resin is now completely orange!

God only knows what was residing in that tube. It's the same house, the same water system.....just a different tap and pipe. If I had of put that straight into the tank and just added salt and a dechlorinator I would have likely killed everything in it.

Now I need to pickup a new DI filter and will be running that tap for a while when I get home to hopefully clean it out a bit. Not all water is created equal

 

[Kurt_Nelson]

... Or it could just mean that your RO membrane isn't working right after the move and your DI is doing 100% of the work.

 

[Jaybird]

There's no way to botch it up. The whole unit is mounted to a metal bracket. moved the whole assemby to two screws on the wall. Connect the input to the water faucet....red tube is RO and blue is RO/DI.

The only difference was location and where the water was drawn from. That tap hadn't even been turned on since the the beginning of September.

 

[Kurt_Nelson]

There's no way to botch it up. The whole unit is mounted to a metal bracket. moved the whole assemby to two screws on the wall. Connect the input to the water faucet....red tube is RO and blue is RO/DI.

The only difference was location and where the water was drawn from. That tap hadn't even been turned on since the the beginning of September.

So it's not possible for something that was in the stagnant water to foul the membrane itself? OK.

 

[Jaybird]

That's exactly what I said. A different tap that hadn't been used for a long time had enough built up in it to finish 75% of my di filter making only 4 liters

 

[Kurt_Nelson]

Hmmm... not sure how else to put it. I'm not arguing that the water was nasty, but am debating what really caused what to happen.

Let's just say that I'd keep an eye on the rate of depletion of your DI resin. If it stays high, then take a look at your membrane - you might have issues.

 

[jim692]

Jaybird,
You didn't say if you flushed the line before you hooked up the unit?

P.S. is your water from a well, municipal or other source?

 

[Jaybird]

Nope, I didn't flush it first. I'm on municipal water. Because I didn't flush the line it killed my DI filter.

That's the point of the warning. I didn't think to flush it before hooking up the RO/DI system. If I had of just run that into a container, added salt, and put that in the tank it would have been exactly like that movie 2012....explosions and all !

I'm going to order two new DI filters for the system.

 

[jim692]

It's not the water. It's possible the line had alot of sediment in it when you hooked up your unit.
Then you hooked up and sucked all the "stuff" into your unit with the water.
Depending on the make up of your pipes, (copper, brass, plastic, or steel), they will all collect debris and scale differently based on their age.
Flush your pipes but more importantly you want to flush the main line into the house off the street main.
Do that by opening all the faucets, hose bibbs, etc. you can. Run them for 4-5 minutes.
You basically want the velocity of the water in the pipe to exceed 10 ft/sec of flow. At that rate all debris in the pipe will be pulled out.

 

[fort384]

it would have been exactly like that movie 2012....explosions and all !

Nice...

 

[WhiteDevil]

Even two months of not using it shouldnt have had that much build up in it, it takes a while for that to build up on city water.

what else is supplied off that water line? they connect somewhere in your house, find the closest faucet, turn the water off at the main coming into your house, and backflush your lines, just open the one closest to that spiggot you used to hook your unit up to.

Ive done ALOT of plumbing work with my grandfather and even the cabin with city water we didnt use for over two years didnt have any build up in it.

what color is the water coming out of that supply line? I think your unit is messed up not your line, every time you use water in your house it pressurizes the lines and always has fresh water in it. Im just saying two months will not cause a build up like that, even with well water( unless its a very rusty well then you got more issues then worrying about a RO/DI unit)

I had a 3 filter RO/DI unit for about 10 years in my house, I recently ripped it out and threw it away(mainly due to being outdated and filters and resin were really hard to find for this unit) I just buy spring water now for 39c a gallon, fish seem to respond to this water better.

The only pipes I know to turn sediment orange is iron, copper turns green and brass does as well( I think brass does, I havnt seen that used on residential plumbing in a long time.

 

[jim692]

Normally thats true Whitedevil,
But things can churn the sediment in the street mains like fire hydrants, city pumps, fire sprinklers, etc. If you turn on the tap you pull it into your house piping. Flushing the pipes will rule any more debris from the lines as an issue. Then he can focus on the unit.

 

[WhiteDevil]

Usually its settled and its only stained water that comes out. They must have replaced a main somewhere on his supply to kick that much up in that short amount of time.

I know turning the tap on but there should have been enough backpressure to wash the sediment into the other faucets.


Did you(thread author) notice any discoloration since sept coming out of other faucets?

 

[gzeiger]

All that debate aside, I'm not convinced that the RO unit is undamaged, although I will concede the possibility that bad water was the cause of the damage. The DI resin is not supposed to be doing all the deionizing - the RO membrane should remove nearly all the ions. Significant breakthrough suggests to me that the membrane may be punctured, possibly due to rust particles. Replacement of the resin will tell you real fast if that's the case, so keep us updated.

 

[Jaybird]

I went to one marine-only dealer on Friday and they don't carry the Pure-Flo II unit or membranes, so I tried the Big Al's on the way home from work. The person I talked to there didn't know what an RO/DI unit was. I showed her the same unit in the corner of the store and she couldn't find any extra filters. I thought I would have had to get them online but I called the west-end Big Al's and they had one DI filter in stock.

I bought the filter yesterday and have run the faucet (flushing the water outside using the garden hose) and have replaced the filter and have run the unit for about an hour. The DI gel is as green as it was when it went into the unit.

I'm now filling up my pop bottles so that I can do top-ups on my tank. I usually go through about 4L of RO/DI water per day. As we move into winter here the air gets extremely dry, which will speed up the evaporation.

There had to be something in that initial surge of water from the tap that passed the main membranes. Perhaps it was a build-up of metals in the tube...who knows. It seems fine after it's been flushed.