[Bob I]

I changed all of the filters in my RO unit, including the RO membrane, and the TDS are still near 100. The TDS are 0-8 coming directly out of the RO membrane housing, 50 going into the tank, and 98 when the water comes out of the faucet. I can't figure out where the water is getting the TDS in between the membrane and the faucet. Any ideas would be appreciated. Thanks

[gaindauz]

I copy this from my RO System manual. This for first time use and after change the filter. Maybe it can help you.

A.With everything connected, turn on the water check for leaks.
B.Make sure the storage tank shut-off valve is "OFF". Open the sink
top faucet.
C.Within a few minutes (up to 15) the water will start to run from the
faucet slowly.
D.Let the water run for at least 30 minutes. This flushes the carbon
filters on first time use.
E.After initial flushing, open the shut-off valve on the tank and close
the sink top faucet.
F.Tank will now full of water (usually 2 to 3 hours) after the tank has
filled. Open the sink top faucet and drain all water until the storage
tank is empty and there is only a small flow from the sink top
faucet.*** DO NOT USE FIRST TANK OF WATER.***
G.Close the sink top faucet. The system is now ready for use.
H.Change filters regularly every 6 to 12 months and have the
membrane checked annually.

[Bob I]

I actually did all of that when I installed the filters. I've run 4-5 tanks of water through not without any better results. The filters seem to be working fine since the water coming out of the RO membrane exit port read 0-8 for TDS. I'm picking something up someplace after the water is clean. I can't figure out if I'm getting bad water in the system somehow (doesn't seem likely since I don't see any way for either untreated or waste water to be introduced), or possibly a faulty component (auto shut-off valve or?).

[gaindauz]

Your membrane work fine.
Any other filter installed after membrane? if have, try to remove it.

[in10ceguy]

Originally Posted by Bob I

I changed all of the filters in my RO unit, including the RO membrane, and the TDS are still near 100. The TDS are 0-8 coming directly out of the RO membrane housing, 50 going into the tank, and 98 when the water comes out of the faucet. I can't figure out where the water is getting the TDS in between the membrane and the faucet. Any ideas would be appreciated. Thanks

how accurate is your tds meter?
if it is a dual tds ...i would calibrate both readings