dngspot
Well-known member
- Joined
- Jul 7, 2006
- Messages
- 82
After building my auto top off I eliminated the constant cycling that the RO/DI did with a float valve. This was a major improvement and has reduced how often I had to replace the DI resin. Yet looking at my TDS meter I have seen TDS creep as high as 250. It takes 5 minutes to remove the saturated water from the membrane, then it is sent to my DI canisters and they take care of the TDS saturated water. The DI resin taking care of the creep shortens the life of the resin as most of you know.
My solution is a simple device. It uses a relay, two solenoids and a delay to make switch. The schematic should explain the electrical side of the assembly. The run solenoid is placed after the DI canisters and the flush solenoid is placed before the canisters on a tee and its drain line is tee'ed into the waste water line on the ro.
The way the thing works, the auto top off sends 120vac to the flush assembly. 120vac hits the Delay to Make switch and the naturally closed contact on the relay then off to the flush solenoid. The flush solenoid opens and water flows from the ro to drain. After 6 minutes the delay to make switch closes and the relay is energized. 120vac moves to the energized contact and voltage removed from the flush solenoid and sent to the run solenoid. Water now flows through the DI canisters then through the run solenoid and off to my display.
Here is my hand drawn schematic.
The actual device works great but looks terrible. I built is with stuff that I had lying around. The relay is way over kill, it is one left over for my MH setup. The solenoid was used on my calcium reactor for a bit, I replaced it with a better one. The delay to make switch came from a friend, thanks David. Normally I would have put this on a project board and in a project box, like my auto top off, seen on the left but, like I mentioned it was built from stuff left over from other projects and is hidden in the basement.
This thing feeds from my electric auto top off. Here is a link to its build
http://www.wichitaaquariumclub.com/forums/showthread.php?t=599
DIY Auto Top Off - Wichita Aquarium Club Forums
My solution is a simple device. It uses a relay, two solenoids and a delay to make switch. The schematic should explain the electrical side of the assembly. The run solenoid is placed after the DI canisters and the flush solenoid is placed before the canisters on a tee and its drain line is tee'ed into the waste water line on the ro.
The way the thing works, the auto top off sends 120vac to the flush assembly. 120vac hits the Delay to Make switch and the naturally closed contact on the relay then off to the flush solenoid. The flush solenoid opens and water flows from the ro to drain. After 6 minutes the delay to make switch closes and the relay is energized. 120vac moves to the energized contact and voltage removed from the flush solenoid and sent to the run solenoid. Water now flows through the DI canisters then through the run solenoid and off to my display.
Here is my hand drawn schematic.
The actual device works great but looks terrible. I built is with stuff that I had lying around. The relay is way over kill, it is one left over for my MH setup. The solenoid was used on my calcium reactor for a bit, I replaced it with a better one. The delay to make switch came from a friend, thanks David. Normally I would have put this on a project board and in a project box, like my auto top off, seen on the left but, like I mentioned it was built from stuff left over from other projects and is hidden in the basement.
This thing feeds from my electric auto top off. Here is a link to its build
http://www.wichitaaquariumclub.com/forums/showthread.php?t=599
DIY Auto Top Off - Wichita Aquarium Club Forums
