RO/DI unit

This was all done via correspondence with AWI. I have an inline temp probe in the intake line to make sure a steady temp goes through. Appreciate the concern.

 

I have a 75GPD...On average, 20 min per gal. Just do the math 75/24hrs is 3.1 GPH or about 20 min.

 

nice

 

Tempering or blending hot and cold water is highly discouraged!
Remember being in the shower when someone flushed the toilet of started filling the washer.....You got scalded. The same thing happens with the RO membrane and it cannot take any water over 113 degrees or it melts the glues and thin film fabric. A membrane is very fragile.

All membrane manufacturers test and rate their output at 77 degrees F. Dow Filmtec uses 50 psi, GE and Applied Membranes use 65 psi. This is why a 100GPD GE is actually the same as a 75 GPD Dow.

If cold water temperature is an issue its best and safest to increase the pressure rather than try to increase the temperature for several reasons. One is colder water treats better and will give you lower finished TDS than warmer water, another is the possible damage to the membrane from hot water exposure. This can be done with a booster pumps such as the Aquatec 8800. Another item that helps if and only if you have a drinking water type pressure tank is a permeate pump, it reduces waste and increases production by using the backpressure in the tank to help drive water through the membrane and really works.

Russ at www.buckeyefieldsupply.com , another very reputable vendor who has been around for years has a nice calculator at hthe top of their page which lets you play with pressures and temperatures to see what effects they have on output.

Spectrapure has a worksheet you can walk through which also takes into account osmotic pressure and can be found at the bottom of the paragraph titled "How To Calculate Actual Performance For A Reverse Osmosis Membrane" here:
FAQ FOR REVERSE OSMOSIS

or here:
http://www.spectrapure.com/CALC-FORMULA.pdf