H@rry
Troll
This might be a long post but I want to make sure that I tell everything as accurately as possible. I need help figuring out why my RO membrane does not last very long.
I bought a Spectrapure 5 stage RO/DI unit in 1999. It has a sediment filter, carbon filter, RO membrane, and two DI chambers. Between the two DI chambers there is a sensor to a simple little meter with a push button that gives a green light / red light condition to indicate when the media in the first chamber needs replacing. The instructions say to remove the first chamber, replace it with the second chamber, and replace the media in the first chamber and place it back as the second chamber. For a long time that has worked well. In addition to checking the DI resin, you can remove the cartridge in the first DI chamber, place the empty chamber back on the unit, change some dip switches in the indicator meter, and tell when the RO membrane needs replacing.
The problem is that the system is burning through DI resin about every two weeks. The RO membrane was replaced on 6/13/13 with a new filmtec 100 membrane, .5 micron sediment filter, carbon filter, and it already indicates needing replacement.
I questioned whether the meter is accurate any more so I bought a TDS meter. It came yesterday. My tap water reads 95 ppm and coming out of the RO membrane reads 49 ppm. After the two DI cartridges it reads 0 ppm.
I use about 55 - 60 gallons of water a week. The unit originally came with a 60 - 75 gpd (can't remember) membrane and several years ago I replaced it with a 100 gpd membrane and the appropriate flow restrictor.
About two years ago I installed one of BRS's float valve and shutoff devices because I was always letting the reservoir overflow. Needless to say, my wife was never pleased when this happened. At the same time I installed a flush valve. I would flush it for 5 - 15 minutes a day. This was when I first noticed that the membrane was not lasting like it was at one time. I thought about it and decided that leaving it flushing for that long was depleting the carbon in the filter and letting chlorine through that was destroying the membrane. I started flushing for only a 10 - 15 seconds a day. No difference.
I called the local utility company to see if they had changed to chloramine. Nope, still on chlorine.
The last time I replaced the membrane I tried to see if I could see anything in the housing like scratches or grooves but could see none.
Anybody got any ideas?
I bought a Spectrapure 5 stage RO/DI unit in 1999. It has a sediment filter, carbon filter, RO membrane, and two DI chambers. Between the two DI chambers there is a sensor to a simple little meter with a push button that gives a green light / red light condition to indicate when the media in the first chamber needs replacing. The instructions say to remove the first chamber, replace it with the second chamber, and replace the media in the first chamber and place it back as the second chamber. For a long time that has worked well. In addition to checking the DI resin, you can remove the cartridge in the first DI chamber, place the empty chamber back on the unit, change some dip switches in the indicator meter, and tell when the RO membrane needs replacing.
The problem is that the system is burning through DI resin about every two weeks. The RO membrane was replaced on 6/13/13 with a new filmtec 100 membrane, .5 micron sediment filter, carbon filter, and it already indicates needing replacement.
I questioned whether the meter is accurate any more so I bought a TDS meter. It came yesterday. My tap water reads 95 ppm and coming out of the RO membrane reads 49 ppm. After the two DI cartridges it reads 0 ppm.
I use about 55 - 60 gallons of water a week. The unit originally came with a 60 - 75 gpd (can't remember) membrane and several years ago I replaced it with a 100 gpd membrane and the appropriate flow restrictor.
About two years ago I installed one of BRS's float valve and shutoff devices because I was always letting the reservoir overflow. Needless to say, my wife was never pleased when this happened. At the same time I installed a flush valve. I would flush it for 5 - 15 minutes a day. This was when I first noticed that the membrane was not lasting like it was at one time. I thought about it and decided that leaving it flushing for that long was depleting the carbon in the filter and letting chlorine through that was destroying the membrane. I started flushing for only a 10 - 15 seconds a day. No difference.
I called the local utility company to see if they had changed to chloramine. Nope, still on chlorine.
The last time I replaced the membrane I tried to see if I could see anything in the housing like scratches or grooves but could see none.
Anybody got any ideas?
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