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Float Switches


  1. Float switch source
    by email_user_id/email_address (Sun, 01 Sep 96)
  2. RO filter float valve
    by pprior/ (Paul A Prior) (17 Aug 93)
  3. Top Off Controller, Suggestions?
    by ()
  4. DIY Float Switch, Waterchanger, Solenoids
    by Wright Huntley <huntley1/> (Sun, 11 Feb 2001)

Float switch source

by email_user_id/email_address
Date: Sun, 01 Sep 96

a company called omega (1-800-826-6342) has a complete line of very small and inexpensive float
switches.  they also carry a complete line of instrumentation for all types of measurements
(flow, temperature, ph, etc.). they also have engineering support if you have implementation

RO filter float valve

by pprior/ (Paul A Prior)
Date: 17 Aug 93
Newsgroup: rec.aquaria

In article <> (Nick Ullman) writes:
>I just hooked up a simple float valve in my resevor tank where I keep
>my supply of replentishing and water change water.  My idea was that
>I could turn on my RO filter and forget about it because a couple of
>times I did (without the float :^( )

Been there, done that.

>Things worked great until I realized that, while the supply line from
>the RO was stopped, the waste line was still flowing.  My understanding
>of how an RO works says this is correct (right?).
>Is there a way to plumb an RO unit to do what I am trying to do?

Hmmm... you should not have that occuring.  I have a similar setup,
though my shutoff is via a solenoid valve, and when the flow stops
the RO unit the water will flow for a few seconds (long enough for
back pressure to build up) and then it shuts off.

BTW, I -really- like my system - it is an air column pressure valve
(about the size of a drinking straw) that sits in the corner of
my sump (fully adjustable) which turns on and off a solenoid valve.
When the water in the sump goes down (I use evaporative cooling
in the summer, so this can be quite a bit in a 150 gallon tank)
it kicks in and keeps the sump level constant - I never add water.
It was built for me by Charles Mitsis of SpectraPure (in FAMA) after
an earlier electrode based unit failed to shut off properly (salt
residue).  I think he now sells them, though they are not in the ads. 

What brand is your RO system?  I think you could get a flow restrictor
valve if it doesn't have one (sounds like it doesn't) to make it
function like the one I have.  Again, I like SpectraPure for their
products and service.  NUmber, if you are interested, is 

I have no affiliation with spectrapure, other than being a very
satisfied customer who likes to see a business who treats their
customers right prosper.

-- 621-8240----------------
Paul A. Prior -- Med III        I am Homer of Borg...               | |
Ohio State College of Medicine   resistance is fut..      Check  --=oOo=--
Happy user of OS/2 2.1!          hmmmm...donut!....        six!    +  

From: (Paul A Prior)
Date: 30 Dec 1993 06:48:17 GMT

Top Off Controller, Suggestions?

Newsgroup: alt.aquaria

In article <2ft62l$> (JEFF PFOHL) writes:
>Does anyone have an automatic top off controller that mounts in their
>sump that they love or hate? I prefer one that will fill automatically
>based not on a preset amount but on the amount actually lost by the
>tank. This leads me to believe that I need a float switch of some
>sort. I appreciate any advice that you can give me. THANKS!! Also, do
>you fill the reservoir with salt water of the proper salinity or just
>pure fresh water since a tank loses water but not salt and thus the
>salinity rises as water evaporates? 

I -=LOVE=- my air-column solenoid valve unit from SpectraPure 
(800-685-2783).  It takes up only about 1/2" of space in the sump,
is fully adjustable, and is electronic (not float) based for 
increased reliability.  I hook it directly to my RO unit and
NEVER have to add water manually.

-- 621-8240----------------
Paul A. Prior -- Med IV          I am Homer of Borg...            + | |
Ohio State College of Medicine   resistance is fut..      Check  --=oOo=--
Happy user of OS/2 2.1!          hmmmm...donut!....        six!      

DIY Float Switch, Waterchanger, Solenoids

by Wright Huntley <huntley1/>
Date: Sun, 11 Feb 2001

> Date: Sun, 11 Feb 2001 07:26:18 -0500
> From: Dwight <>
> Subject: DIY Float Switch, Waterchanger, Solenoids
> I'm curious to know if you Do-It-Yourselfers have developed your own Float
> Switch, Waterchanger, Solenoids system.  If so, did you find it easier to
> build your own from scratch or buy a pre-assembled brand.

The parts would cost me far more than the whole valve assy., so I bought
> How reliable was/is your system? 

100%, so far.

> How much did it cost?

$5-6 at Ace Hardware (if I bought new)for the float valve. Found a bunch at
a junk shop for $0.50 each.

> What is your parts/component list? 

For just the fill system?

One swamp-cooler float valve* and a refrigerator ice-maker installation kit,
plus 2 drip-irrigation barbed valves. Total cost about $15. One drip valve
was to slow the flow through my carbon filters to be sure to catch all the
chloramine. The other was to test the water between two filters to see when
chlorine is punching through.

> In terms of cost,value & reliability, what's the best way to go?

I'm happy with my system. I actually have two 40G Rubbermaid heavy-duty
covered barrels and do both tap (carbon-filtered) and RO storage in them
with a float valve to keep each full. A small submersible waterfall pump is
dropped into the desired barrel to deliver water to any tank in the house,
via 1/2" clear tubing. X-10 controller lets me turn on and off from
anywhere. Beats solenoids, hands down, around water.

> Any pictures?:-)

I have some, but they aren't up anywhere. Would not help much, IMHO.

The swamp-cooler valves will be special order in those parts of the country
with higher humidity. I drilled the sides of the plastic barrels and
installed them right through the side, just as they would be on the sheet
metal of a swamp cooler. I did them high, but right by the handles to be
sure they were rigid enough to turn off for sure.

My best gadget addition, recently, was a plastic horse-trough float valve
for about $15 mail order (Libertyville Saddle Shop -- I put some rigid PVC pipe together, with a
friction-fit stopper disk, that lets me set it to fill a tank to whatever
height I want, and forget it. NO MORE wet carpets! The assembly is due to be
published in an upcoming BAKA newsletter, so I guess I should wait to post a
picture of it, too.


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