RO membrane plumbing connection?

[Hunt4sap]

How do I know which port on the bottom of ro membranes is which? ( Water or sap)? I have 4 100 Gpd membranes I want to connect in series...
Thanks fellas!

[wmick]

Not sure what your housing looks like, but the inlet of sap should go to the outside of the membrane, and the water will come out from the center of the membrane.

[Hunt4sap]

Ok. Looking at other sap ro setups being made I see the use of 3/8" pex from pump inlet/ outlet, through pre-filter and in some components...
If all my membrane housings are only 1/4" will the system still get the right flow and output for it to work or is the portion I'm referring to ( like bucket ro sells) done for pressure important reasons?

[wmick]

Ok. Looking at other sap ro setups being made I see the use of 3/8" pex from pump inlet/ outlet, through pre-filter and in some components...
If all my membrane housings are only 1/4" will the system still get the right flow and output for it to work or is the portion I'm referring to ( like bucket ro sells) done for pressure important reasons?

If it is just a short chunk of hose or two, after your hi-pressure pump to membranes, I don't think upsizing the line, will make much difference, being your fittings are 1/4" anyway,.... but on the low pressure side, (before your hi pressure pump), you may want to upsize... to avoid cavitation.... It is difficult for a pump to "draw" liquid into its intake... you want to help it all you can with bigger lines and head pressure. If it is pumping liquid away faster than it can easily take it in, it will cavitate... creating air bubbles and pump damage.

That being said.... bigger is always better... to avoid restriction anywhere in the system.

[Hunt4sap]

Okay thanks. My next thought to eliminate possibility of freezing while running overnight in my unheated sugar shack is to put my sap ro system in my basement where it stays around 60-70 degrees and keep the sap depending on temperature either outside if not freezing or being put in our garage that stays around 50 if freezing overnight? (I guess what I'm asking is what's the best temperature to run sap through an RO?)What do people use for their bulk tank for raw sap?

[Jeff E]

The warmer the sap, the better it moves through the RO, BUT, the warmer the sap, the more bacteria grows. If I had to pick an ideal temp, I would say no more that 50 Deg F. Unless you can run it all through and get it to the evaporator in a few hours.