[RE-wrenches] tankless hot water and pumping question

[Phil Undercuffler]

<snip> off grid with water being trucked in and stored in a ground level
polyethylene tank.

<snip> My building inspector does not allow grade level tanks as the
warm temp adds to bacteria growth. 

 

I agree with Darryl about putting the tanks underground, otherwise they
become veritable cornucopia of bugs and nasties.  Having lived 14 years
off of rain water catch in NM (supplemented with my fair share of hauled
water) I strongly suggest adding a simple low water indicator LED to
give a warning before the tank runs dry.  Otherwise I guarantee the pump
will begin to spit air just when you are standing in the shower with
shampoo in your hair.  Ask me how I know.

 

The indicator can be a cheap LED from Radio Shack, combined with a
resistor to drop the voltage.  Calculating the resistor value is a
simple matter, given the voltage drop across LED and desired current in
circuit.  For instance, if your LED is rated for 1.7v & 20 mA, and your
design voltage is 30 (highest expected voltage while charging), 

30-1.7=28.3

28.3=IR

28.3/.02=R

R=1415

Therefore, find a resistor with a value near 1415 and wire it in series
with the LED.  I've run the circuit into the house on standard signal
cable (1 amp fuse at the power end, of course) and installed the LEDs
through a blank cover plate somewhere unobtrusive but noticeable inside.
Then, it's a simple matter of tethering a "pump up" (close on fall)
float switch so that it triggers with enough time to plan a water
delivery.  

 

I should also throw in that, having made it through all this time living
off the blessings (and curses) of the Rain Goddess, the big news in the
Undercuffler household is we're finally breaking down and putting in a
well - yep, the driller shows up next week.  Keeping my fingers and toes
crossed for sweet water, close to the surface!

 

 

Phil Undercuffler

Director, Battery-based and Off-grid

Distribution Sales Group

Conergy 

Our World Is Full of Energy

1730 Camino Carlos Rey Suite 103

Santa Fe, NM  87507

p.undercuffler at conergy.us

Direct | 505.216.3841

Toll Free | 888.396.6611 x4841

Fax | 505.473.3830

www.conergy.us

 

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