Mike&Terry
Wrasses, Angels, & Tangs, Oh My!
Thought I'd share a project I did back in 2009.
After spilling more RO/DI water onto my fishroom floor that I care to admit from forgetting to turn off the RO/DI system, I finally decided to build a reliable system to automate the switching. Now I realize that there are various float valves out there to do this, but after trying two with poor results, I decided a more "industrial strength" answer would be better. Plus, I get to DIY and that's what I love about this hobby!
So what this solution gives me is the ability to monitor levels in my R/O Vat, and automatically turn off/on the flow of water into my RO/DI system.
The two core components to this rig are a solenoid valve and an auto top-off (ATO) controller. I went with the polycarbonate solenoid valve with 1/4 inch quick-connects part number 5489T61 from McMaster-Carr. Expensive part, for sure, but the water pressure at my house is crazy high (>80 psi) and I needed something that would stand up to that and be dependable:
And some sort of ATO controller. I just happened to have an old reef fanatic ATO unit laying in the spare bin:
In addition to these, you'll need some sort of moisture-resistant box, an old extension cord, and some terminal quick-connects.
OK, on with the fun. I didn't have a suitable enclosure laying around, so a quick trip to the local rat shack and for $3.99 I picked up this little 5-inch project box:
We're going to mount the solenoid into the box with the electrical connections inside, and the water connections outside. I took the whole thing over to R/O system and figured out how the water lines were running, where I was going to mount the controller, and where the power cords were going to run first. That helped me figure out where I was going to orient the box, and the solenoid within the box. With the dry fit done, I drilled a 1-inch hole in the lid of the project box and mounted the solenoid in there:
Note that you have to take the solenoid apart to mount it. Remove the nut on the top, and pull the poly part straight down from the solenoid and bracket. In this picture I had left the little metal bracket off the solenoid. You must have that on the solenoid or it will not function properly. Also, now's a great time to tell you that the hose connectors on this particular solenoid are labeled 1 and 2. Number 2 is the input side, and 1 is the output side. This is a critical distinction. The solenoid will not function properly with the flow reversed.
Next, we make the electrical connections. Take an old extension cord (I didn't have a spare one laying around since it's Christmas time - those things are like hen's teeth during Christmas - so 97 cents at home depot gets you a six foot cord that works just fine. Chop the receptacle end off of the cord, leaving all the length on the plug piece.
Drill a small hole in the end of your box that will accommodate the cord, and stick it through (leave the plug outside the box, fresh cut wires inside). You need to connect up the cord to the solenoid. Here is where those clamp-style terminal connectors are very handy:
Connect it all up nice and pretty and take a nice in-focus picture of it (ok, maybe not so in focus, lol):
Tighten everything up, close the box, and fasten the lid. Now you got something that is starting to look useful!
r
Now to affix the box to the wall next to my R/O unit. I went with this handy-dandy velcro tape. No DIY-er should be without this stuff!
Next, we need to get the float sensor into the R/O vat. I refuse to depend on those suction cups, because they always fall off at the worst times! So a little dab of silicone sealant on each of the cups makes sure we stay nice and tightly attached to the vat. I used a 3/8-inch bit to drill a hole in the vat lid for the float sensor plug to fit through:
Last thing is to mount the controller safely out of splash range and make all the connections. Bring over the extension cord from the solenoid valve, plug in the float sensor, and hook up the A/C cord for the ATO controller:
Here's the controller taking it's rightful spot overseeing non-spillage!!!
Here you can see the float switches mounted high and low in the vat:
As suction cups do not hold up well over time, I fabricated acrylic holders which have worked great. Here's a close up:
We have since installed a mixing station with 100g vats for RO/DI and saltwater and are still using the same controller.
-Mike
After spilling more RO/DI water onto my fishroom floor that I care to admit from forgetting to turn off the RO/DI system, I finally decided to build a reliable system to automate the switching. Now I realize that there are various float valves out there to do this, but after trying two with poor results, I decided a more "industrial strength" answer would be better. Plus, I get to DIY and that's what I love about this hobby!
So what this solution gives me is the ability to monitor levels in my R/O Vat, and automatically turn off/on the flow of water into my RO/DI system.
The two core components to this rig are a solenoid valve and an auto top-off (ATO) controller. I went with the polycarbonate solenoid valve with 1/4 inch quick-connects part number 5489T61 from McMaster-Carr. Expensive part, for sure, but the water pressure at my house is crazy high (>80 psi) and I needed something that would stand up to that and be dependable:
And some sort of ATO controller. I just happened to have an old reef fanatic ATO unit laying in the spare bin:
In addition to these, you'll need some sort of moisture-resistant box, an old extension cord, and some terminal quick-connects.
OK, on with the fun. I didn't have a suitable enclosure laying around, so a quick trip to the local rat shack and for $3.99 I picked up this little 5-inch project box:
We're going to mount the solenoid into the box with the electrical connections inside, and the water connections outside. I took the whole thing over to R/O system and figured out how the water lines were running, where I was going to mount the controller, and where the power cords were going to run first. That helped me figure out where I was going to orient the box, and the solenoid within the box. With the dry fit done, I drilled a 1-inch hole in the lid of the project box and mounted the solenoid in there:
Note that you have to take the solenoid apart to mount it. Remove the nut on the top, and pull the poly part straight down from the solenoid and bracket. In this picture I had left the little metal bracket off the solenoid. You must have that on the solenoid or it will not function properly. Also, now's a great time to tell you that the hose connectors on this particular solenoid are labeled 1 and 2. Number 2 is the input side, and 1 is the output side. This is a critical distinction. The solenoid will not function properly with the flow reversed.
Next, we make the electrical connections. Take an old extension cord (I didn't have a spare one laying around since it's Christmas time - those things are like hen's teeth during Christmas - so 97 cents at home depot gets you a six foot cord that works just fine. Chop the receptacle end off of the cord, leaving all the length on the plug piece.
Drill a small hole in the end of your box that will accommodate the cord, and stick it through (leave the plug outside the box, fresh cut wires inside). You need to connect up the cord to the solenoid. Here is where those clamp-style terminal connectors are very handy:
Connect it all up nice and pretty and take a nice in-focus picture of it (ok, maybe not so in focus, lol):
Tighten everything up, close the box, and fasten the lid. Now you got something that is starting to look useful!
rNow to affix the box to the wall next to my R/O unit. I went with this handy-dandy velcro tape. No DIY-er should be without this stuff!
Next, we need to get the float sensor into the R/O vat. I refuse to depend on those suction cups, because they always fall off at the worst times! So a little dab of silicone sealant on each of the cups makes sure we stay nice and tightly attached to the vat. I used a 3/8-inch bit to drill a hole in the vat lid for the float sensor plug to fit through:
Last thing is to mount the controller safely out of splash range and make all the connections. Bring over the extension cord from the solenoid valve, plug in the float sensor, and hook up the A/C cord for the ATO controller:
Here's the controller taking it's rightful spot overseeing non-spillage!!!
Here you can see the float switches mounted high and low in the vat:
As suction cups do not hold up well over time, I fabricated acrylic holders which have worked great. Here's a close up:
We have since installed a mixing station with 100g vats for RO/DI and saltwater and are still using the same controller.
-Mike
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