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RSOMOGYI
01/11/2009, 08:02 PM
I need Help.

I just purchased a water filtartion system, RO/DI.
I have assembled the unit and started running the unit. My question is this. The waste line seems to continue to run. I can't tell if the tank is filled or not. When I close the tank valve then the waste line stops running. I isn't the autofill because I verified that it is working correctly. I checked to be sure that all was in the correct flow position. Sorry that I am all over the place. Is this normal?

The good part is this: 301 ppm in / 000 ppm out

AZDesertRat
01/12/2009, 08:10 AM
I assume you have a system with a pressure tank and auto shutoff valve? If so you confirmed it is working correctly when you shut the tank valve off and the waste line stopped too. Thats the purpose of the autoshutoff valve (ASOV), it shuts flow to both when it senses backpressure from a full pressure tank, raised float valve, closed ball valve or solenoid valve. If the waste is running the pressure tank is filling.

RSOMOGYI
01/13/2009, 08:55 PM
OK =I have done some research in the meantime. What I failed to mention is that my water pressure is only 40 psi. My understanding is that the unit will not work properly with a psi so low. So what is the best way to raise the water pressure, with a permiate or a small booster pump? I have read pros and cons. I would rather have real reality information.

das75
01/13/2009, 09:45 PM
still will work with 40psi, just not as well as a higher pressure.

Here's (http://www.freedrinkingwater.com/infocenter.htm) a link that has a couple of plots (towards to bottom) that gives an idea of the effects of pressure and temperature.

A.T.T.R
01/13/2009, 10:07 PM
the auto shut off will still work ( since you proved it by shutting off flow to tank)
whats the TDS before the DI if its low you may not need to worry about hte low pressure

RSOMOGYI
01/13/2009, 10:26 PM
coming in from outside - 360 ppm
after the 3 white filters and the RO (white canister)- 85 ppm
after the DI - 27 ppm
This is odd because last night I was at 0 ppm after the DI.
This is begining to get very futrating.

AZDesertRat
01/14/2009, 07:53 AM
Let the system run for several minutes before testing.
How are you testing and where are you testing from. If you have a storage tank, do not store DI water in it. Use the storage for RO only and install a tee and ball valve off the RO output line to get DI water. TDS accumulates in a pressure tank due to frequent starts and stops and what is called TDS creep or the initial high TDS that a membrane produces on start up.
40 psi is about the bare minimum pressure you can get by with. The production will be painfuly slow and with the pressure tank the waste will be quite high. Higher pressures not only make water faster they also produce higher quality water.

To get an idea of the effects that pressure and temperature have on RO production look at the calculator at the top of the page here:
www.buckeyefieldsupply.com

Plug in your pressure and water temperature and its very accurate.

I hope for your sake the readings you provided for the RO only and DI are not correct. They should be about 8-12 for the RO only and 0 for the DI.

RSOMOGYI
01/14/2009, 08:00 PM
I am using 2 Dual TDS Meters.
I am testing the water coming in before going into the filtration unit, which is reading at: 286
Then right after the RO unit which is reading: 44
Right after the DI: 000
I also put a Meter at my waste line: 296
This is after the unit ran for 5 minutes.
My static pressure is 40 psi, when the filtration is running it drops to 28 psi. So how can I get this unit to run more efficent?
One other thing. When I had the carbon filter on the PPM jumped up - is this because I didn't fully flush this cartridge? I took it off for now. Should I be using the carbon filter also? Any and all info is great appreciated. Thanks.

AZDesertRat
01/14/2009, 09:17 PM
Calculate your waste ratio. Use a measuring cup and watch or clock and see if its close to 4:1 waste to good. I suspect its much higher than that according to your waste TDS number and your significant pressure drop. I only see a 1-2 psi drop across the filters between static and operating pressures. The waste should also be about 25% higher than the tap water TDS so in your case it should be more like 350 or so.
Both the pressure drop and low waste tDS are indicators of a high waste ratio. I'll bet once the waste is set correctly you will see an increase in pressure available to the membrane, higher water quality and higher GPD.

RSOMOGYI
01/15/2009, 06:16 PM
How do I set the waste water line corrrectly, I am not sure what you mean.
I seen some info as to buying a booster pump and or a premait pump ... not sure of the spelling. What is the difference, and the pros and cons.