On Sep 17, 8:37*pm, "Michael A. Terrell"
wrote:
wolfgang wrote:

On Sep 16, 2:00 pm, " wrote:
On Sep 15, 8:17 pm, wolfgang wrote:

To run the pump is about $400 for 6 months. *I've tried to put the
pump on a timer but during hot weather the water doesn't like it and
turns green. *I'm afraid to cycle the pump more than once every three
hours or so as this shortens the starting switch life expectancy.

Wolfgang

A *thought. *Could you connect a lawn sprinkler to the output of the
pump and have its output come down into the pool. *The water droplets
would adsorb oxygen in the air and the agitated pool surface would
also add oxygen to the pool.

My understanding is that releasing air at the bottom of the pool does
not work so well. *Too much nitrogen gets adsorbed by the water.

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *Dan

Thanks for all those suggestions, they are greatly appreciated!

Currently I have a floating chlorinator that I fill with 3" dia.
"pucks" every 10 days or so. *For July and August I also add an
algicide. *I used to have an automatic chlorinator, also with pucks,
but it was very difficult to keep the chlorine level properly
adjusted.

Spraying part of the returned pool water through the air to absorb
oxygen can be done with a small pump while the main pump is shut off.
Running the main pump 4 to 6 hours per day sounds REALLY appealing!

Ozonation is another item to look into. * I seem to recall that this
method is also used for drinking water treatment in some areas?

All good stuff. *Thanks again.

* *I did that for a neighbor's fish pond to control the algae. *It
worked great, till someone talked her into some plants that were
supposed to do the same thing with less water loss. They ripped out what
I'd built and made their changes. *It was completely green again in a
couple weeks. *I had built a small waterfall out of rocks, about 24"
high and a foot wide.

--
You can't have a sense of humor, if you have no sense.


Pool pump efficiency stinks!

Yesterday I measured the current draw of my 3/4 HP pool pump. Meter
read 8.8 amps, and the name plate states 13.8 amps full load current.
Doing some calcs I determined that at that operating point of the
motor the electrical efficiency is 35%! Something clearly needs to be
done. (knowledgable electric motor guys may wish to chime in on this,
please). I think that maybe a 1/2 HP pump would suffice? The suction
line is 1 1/2" dia. with 3 elbows and about 40 ft in length.

I was perusing a pool maintenance website and the moderator
recommended that the pump be run at least 6 hrs per day.

Since it is too late in the season to do much with the pool (I close
and winterize it on the Labour Day weekend) I have put the timer back
in the motor circuit and set it such that it cycles 4 hours on and 4
hours off; thus cutting the power consumption by almost 50 %.

For next year I will do the same while investigating better electric
motor efficiencies and how to achieve this. Perhaps by using algecide
earlier and more regularly in the season the algae can be avoided with
cycled pump times.

I'd be interested in learning much more about motor efficiencies and
how to achieve this; any recommended readings are greatly
appreciated! ****, one can buy electric model motors running at tens
of thousands of RPM with 90 % efficiency, dirt cheap.

Wolfgang