Home built RO - Working out details

[mol1jb]

Hey all,

So I said I wouldn't do it but the more I read and research the more I think I can put a homemade RO together. I understand all the main components but I need some help with the details of the machine. If I spend the time and money on this I want to do it right with all the high/low pressure shutoffs and high temp shutoff. The location of these switches in the plumbing I am not sure about. From what I have read the low pressure shutoff goes after the filter and the high pressure shutoff goes after the booster pump? The high temp shutoff I have no idea.

18630

Procon material - Brass vs stainless. I will be using a 330 gph pump to power one 4x40 with probable adding a second tower as tap count increases. Brass procons are used in some of the commercial units and I have the ok from the health department who inspects our kitchen that brass is acceptable. Now if money was no object I would go stainless but they are about double the price form the brass procons. Thoughts?

Motor - From what I have read 1.5-2hp motor will run two 4x40 well. Am I in the ball park?

I'm sure I'll have more questions but that is all for now.
Thanks,

[Urban Sugarmaker]

Your setup is correct, but I think you'll want your high pressure gauge after the pressure pump but before the membrane inlet. There is a pressure drop across the membrane and if you are measuring concentrate output pressure it's going to give you the wrong info, ie membrane pressure is higher than indicated.

I have a 1.5 HP motor running a 330 GPH Procon (stainless) and I plan to add another 4x40 for 2019. Pump output vs. pressure and required horsepower can be found on Procon's website here https://store-c59cb.mybigcommerce.com/content/Series%205%20Pump_spec.pdf

1.22HP is required for the 330 pump at 250 PSI.

On mine, the high pressure shutoff switch is just after the procon outlet. I used pressure switches from Automation Direct. They are fairly pricey but reliable and high quality.

I went with stainless on the Procon just because everything is going that direction.

My high temp is just after the low pressure switch which are both after the pre-filter. I used a 3/4" RTD probe and temp controller form Auber Instruments.

[mol1jb]

Thanks for the reply,

For plumbing in the rinse and wash lines - Would those be plumbed into the intake line after the filter? I should preface that this unit will be stationary unit inside a RO closet drawing from stationary tanks.

[Urban Sugarmaker]

Everything that is going to go through the RO membrane should be pre-filtered including rinse/wash. I use and re-use a 5 micron filter for rinse and wash. You probably shouldn't use the pre-filter you concentrated with on rinse/wash cycles.

[mol1jb]

Ok so the intake line from the sap tank will be 1" into the pre filter. Then at some point it will have to reduce to 1/2" to feed the procon. At what point is it best to do this? I was thinking to do that at the procon inlet.

[Urban Sugarmaker]

Yes, that's where I did it but I used barbed fittings for the hose into the procon.

[mol1jb]

For tubing and fittings - I will need high pressure fittings and tubing from the procon outlet to the membrane and from the membrane to concentration needle valve? Also the recirc line and fittings needs to be high pressure rated?

[maple flats]

If your recirculation line has no shut off valve after the needle valve you do not need high pressure tubing there. The inlet is HP but the other side a rather low pressure, as it feeds the HP pump. The exception might be if you have a HP recirc. pump, but that is unlikely, especially on a home built basic RO.

[mol1jb]

Membrane housing orientation - I have seen them horizontal and vertical. In terms of function is one way better than the other?

Booster pump location in relation to the membrane - Most RO I have seen have had the pump on the bottom of the unit. Would it matter if the pump was in a different location (Along side the membrane)? I assume you want to keep the pump closer to the inlet of the membrane to keep the high pressure hose shorter but I that is only a guess.

Initial flush of the unit - I have well water that goes through a filter and has a chlorine additive. My thought was to fill up my permeate tank a few months prior to the initial flush of the RO in order to let the chlorine reduce over that time. Thoughts on this?

[MunsterMapler]

I'm not sure if it will help or not but I'm in the process of building a homemade ro too. Did a lot of research on this site and got there were some real helpful threads where people basically put a whole parts list out there1864518646
This is what I came up with so far, still waiting for a few bits and pieces but almost done.
http://mapletrader.com/community/showthread.php?29171-100-GPH-RO-Build-for-2-000-Pics-Video-Diagrams...-Oh-My!/page7

This was one of the threads that was extremely helpful, thanks wood butcher!

[mol1jb]

I'm not sure if it will help or not but I'm in the process of building a homemade ro too. Did a lot of research on this site and got there were some real helpful threads where people basically put a whole parts list out there1864518646
This is what I came up with so far, still waiting for a few bits and pieces but almost done.
http://mapletrader.com/community/showthread.php?29171-100-GPH-RO-Build-for-2-000-Pics-Video-Diagrams...-Oh-My!/page7

This was one of the threads that was extremely helpful, thanks wood butcher!

Thats funny cause I am using the same thread as my build base. Your build looks really good! Anything you changed from wood butcher’s build?

[MunsterMapler]

Yeah I changed a few things around, he has an outstanding parts list to get people pointed in the right direction. I should of got a larger enclosure in hindsight. Mine is a 12x12x6 but should of got like a 16x16x8. Things are a little snug in there but I made it work.