"SMS" wrote in message
...
In the summer I probably lose 150 gallons a day or so to evaporation with
the level falling about 1/4" per day. If it falls below the skimmer level
the pump will such air because the bottom drain is no longer functional.
The problem is when I go out of town for work or on vacation and no one
monitors the pool level.

Yesterday I replaced the manual fill valve with a 24VAC valve and hooked
it to my sprinkler controller so I can add water automatically, but there
is no feedback as to the water level. I'm trying different daily fill
times to find one that maintains the water level relatively constant, but
it's inexact and depends on the weather.

I want to construct some sort of level detector that will cut off the
automatic fill valve if the level gets too high, or I could disconnect the
timer and hook the level detector relay directly to the valve.

I was thinking of this:

"http://www.ingramproducts.com/Pumps_Level_Controls-24_VAC_Multi_function_Moisture_Sensing_Relay.html"

and this:

"http://www.ingramproducts.com/Pumps_Level_Controls-Custom_Sensor_Assemblies_for_Liquid_Level_Control_ 1.html"

In the winter and spring I often have the opposite problem, the pool
overflows from rain, and I'd like to also do something that opens the
pump's drain valve diverter and removes water until the level falls to the
proper level.

A friend of mine has a spendy one that's all plastic, and a real POS. It is
forever falling over, and then the water runs continuously. It is fed by a
simple garden hose. A McGyver type guy could make one simple enough. The
problem is finding a place in the pool where it is protected from rowdy
kids, and having it weighted so that it won't fall over and free flow. I
don't think either problem is insurmountable. As for a way to open the
drain diverter, that would take more machinery, and that could be prone to
failure or mistake, in which case you might just lose several thousand
gallons of water. I'd consider a sensor just like the one that senses low
level, but have that sensor activate a pump to drain the water, and kick off
once the water level is down. If one is an electric type person, a low
voltage sensor should not be difficult, and that can run to either an
actuator to fill, or to a pump to drain.

Steve

visit my blog at http://cabgbypasssurgery.com watch for the book