bellareef
05-30-2008, 08:47 PM
I use a 5 gal bucket as RODI reservoir, with a float valve to keep it full. My auto topoff pumps water from the RODI bucket to the sump, via Kalk mixer.
However, this caused my RODI filter to turn on/off/on/off/on/off frequently, increasing TDS out of the RO membrane (TDS Creep). To make things worse, my RODI filter has a booster pump to increase efficiency, so it was loud & annoying as well.
I'd seen anti-TDS devices advertised, and wanted one, but didn't want to spend $150
http://www.airwaterice.com/product/ANTITDS/Anti_TDS_Creep_storage_tank_18_x_33.html
Here is what I did:
To combat TDS creep, I setup the 5 gal bucket so that it fills with new RODI water only after the bucket gets 95% emptied. This requires an enclosure for the float switch, and a one way air valve connected to the top of that enclosure. No solenoid required.
Think of the float valve enclosure as an "inverted cup in the bathtub", with a one way air valve attached at the top (bottom of cup).
see if I can upload photos...
These 3 ABS parts are available at Lowes.
http://www.premiergroupcare.com/fishpics/TDS/1.jpg
http://www.premiergroupcare.com/fishpics/TDS/2.jpg
http://www.premiergroupcare.com/fishpics/TDS/3.jpg
Float valve enclosure needs to be air/water tight.
http://www.premiergroupcare.com/fishpics/TDS/5.jpg
http://www.premiergroupcare.com/fishpics/TDS/7.jpg
It took some time to figure out an enclosure for the float valve, but found parts at Lowes. I got the float valve from ebay, but might be available locally. This didn't take long to make. Used teflon tape on threaded endcap, so enclosure cover is removable & air/water tight.
At the top, use a one way valve to vent air up and out, so the enclosure can fill with water after it's evacuated (when the bucket gets empty). When the bucket gets empty, air is allowed up thru the hose at the bottom, emptying the float valve enclosure, allowing the bucket to fill up again.
I used zip ties & epoxy (patched small leaks with silicone) to attach threaded endcap to the inside of the bucket.
Have had this running for over a year. Only once had a problem (defective one way valve), which prevented the enclosure from filling, & float valve from sealing--got water on the floor. If you're good with acrylic, a much prettier/space saving rectangular device can be easily made--maybe one day I'll do this. If you make one, please post what you come up with.
http://www.premiergroupcare.com/fishpics/TDS/8.jpg
However, this caused my RODI filter to turn on/off/on/off/on/off frequently, increasing TDS out of the RO membrane (TDS Creep). To make things worse, my RODI filter has a booster pump to increase efficiency, so it was loud & annoying as well.
I'd seen anti-TDS devices advertised, and wanted one, but didn't want to spend $150
http://www.airwaterice.com/product/ANTITDS/Anti_TDS_Creep_storage_tank_18_x_33.html
Here is what I did:
To combat TDS creep, I setup the 5 gal bucket so that it fills with new RODI water only after the bucket gets 95% emptied. This requires an enclosure for the float switch, and a one way air valve connected to the top of that enclosure. No solenoid required.
Think of the float valve enclosure as an "inverted cup in the bathtub", with a one way air valve attached at the top (bottom of cup).
see if I can upload photos...
These 3 ABS parts are available at Lowes.
http://www.premiergroupcare.com/fishpics/TDS/1.jpg
http://www.premiergroupcare.com/fishpics/TDS/2.jpg
http://www.premiergroupcare.com/fishpics/TDS/3.jpg
Float valve enclosure needs to be air/water tight.
http://www.premiergroupcare.com/fishpics/TDS/5.jpg
http://www.premiergroupcare.com/fishpics/TDS/7.jpg
It took some time to figure out an enclosure for the float valve, but found parts at Lowes. I got the float valve from ebay, but might be available locally. This didn't take long to make. Used teflon tape on threaded endcap, so enclosure cover is removable & air/water tight.
At the top, use a one way valve to vent air up and out, so the enclosure can fill with water after it's evacuated (when the bucket gets empty). When the bucket gets empty, air is allowed up thru the hose at the bottom, emptying the float valve enclosure, allowing the bucket to fill up again.
I used zip ties & epoxy (patched small leaks with silicone) to attach threaded endcap to the inside of the bucket.
Have had this running for over a year. Only once had a problem (defective one way valve), which prevented the enclosure from filling, & float valve from sealing--got water on the floor. If you're good with acrylic, a much prettier/space saving rectangular device can be easily made--maybe one day I'll do this. If you make one, please post what you come up with.
http://www.premiergroupcare.com/fishpics/TDS/8.jpg