Just installed a RODI system and from what I have read my output readings should be as close to 0 as possible, my incoming reading is 180-185 ppm and my out going is 5-6 ppm. Is this correct or do I have something wrong? My system is a 4 stage 100 gdp from Buckeye Field and Supply. My water pressure is 58 psi, temp 70 degrees. Advice, suggestions or/and help
TDS readings
- Thread starter Holygral
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DonW
R.I.P.
About how many gallons have you run through it?
Don
Don
DonW
R.I.P.
could be many things...how are you taking your readings? make sure the container you are using to take the readings has been well rinsed using the test water (tap water and dishwasher residue will increase TDS readings by a lot)...also have you calibrated your TDS meter?
MikeS
MikeS
Holygral: as Mike stated, make sure you're using a very clean glass to take your readings. I used to use plastic tupperware, but have been told (and tested to find it true) that plastic container will give you a higher tds reading than a squeaky clean glass.
When taking your sample, let the RODI water run for a while before taking sample, as the 1st that comes out will have a higher tds reading than once the unit has been flowing for a bit.
With filters, RO membrane & DI resin all in good condition, the water after the DI resin should be between 0-1 tds...hopefully 0 or very close. At least that's what I've been reading for 75gpd RODI units.
It might be worthwhile to check with Buckeye to find out what they say their 100gpd RODI unit should produce in regards to tds.
hth,
rob
When taking your sample, let the RODI water run for a while before taking sample, as the 1st that comes out will have a higher tds reading than once the unit has been flowing for a bit.
With filters, RO membrane & DI resin all in good condition, the water after the DI resin should be between 0-1 tds...hopefully 0 or very close. At least that's what I've been reading for 75gpd RODI units.
It might be worthwhile to check with Buckeye to find out what they say their 100gpd RODI unit should produce in regards to tds.
hth,
rob
Last edited:
DonW
R.I.P.
With a incomming tds that low you should easily hit zero. Give it a few more gallons, if you dont get it buy some decent di resin. Most cheap rodi units come with lousy di resin. You can get the good stuff from the filter guys for $8
Don
Don
NaH2O
Well-known member
- Joined
- Jan 25, 2004
- Messages
- 8,568
Holygral - which inline meter are you using? I also use a dual inline meter. The water going into my unit has a TDS of over 500, and 0 coming out. I would follow Don's suggestions and let some more water run through the unit, and see if that helps.
Boomer
Well-known member
I agree with Don
mark peacock
marine67
can some one take a picture of an inline meter so i can see if its like the one i could be getting never seen one before
Curtswearing
Mantisfreak
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=4434270017
This is the meter I am using, there are two dots that are to be aligned between the probe and the T it fits in to, but I notice that misaligning the dots display a wide variety of readings, so I am wondering just how accurate it is. Has anyone else had any experience with this meter and can anyone recommend a good hand held meter to double check my readings? As always Thanks!!
This is the meter I am using, there are two dots that are to be aligned between the probe and the T it fits in to, but I notice that misaligning the dots display a wide variety of readings, so I am wondering just how accurate it is. Has anyone else had any experience with this meter and can anyone recommend a good hand held meter to double check my readings? As always Thanks!!
Holygral: the TDS meter I have is the HM COM-100. I bought it on the advice it is far more accurate than any other consumer grade tds meter available. With that said, I'm sure that comment will open a whole other can of worms 
If you were closer to me, I'd loan mine to you...maybe someone in your area has one you can use to double check the readings.
http://www.purelyh2o.com/product.php?productid=16142&cat=264&page=1
hth,
rob
If you were closer to me, I'd loan mine to you...maybe someone in your area has one you can use to double check the readings.
http://www.purelyh2o.com/product.php?productid=16142&cat=264&page=1
hth,
rob
Thanks Rob
I found it at https://www.wateranywhere.com fo $39.00 and $11.00 ups shipping, I think that I will go that route..........Boy I need about 5 less hobbies!!!
I found it at https://www.wateranywhere.com fo $39.00 and $11.00 ups shipping, I think that I will go that route..........Boy I need about 5 less hobbies!!!
DonW
R.I.P.
That is a fine meter. Mine has run two years. Each time I have tried to calibrate it was dead on. Many people here use them with no problem what so ever.
Don
Thanks Don
I am also ordering a hand help to verify my current readings, this will also allow me to test tap, tank and other paramters, I also have contacted the manufacture of the RO/DI unit and the person I bought the meter from, as I have read some post about bad probes.
I am also ordering a hand help to verify my current readings, this will also allow me to test tap, tank and other paramters, I also have contacted the manufacture of the RO/DI unit and the person I bought the meter from, as I have read some post about bad probes.
