RO advice

[crowellsr]

Next year I'm looking to go to 100-150 taps. I only have 5-6 hours a day that I can boil unfortunately. My 2x4 evaporator will boil 8-10gph. I'd like to figure out what size ro to build that would put out 8ish% concentrate at around the same rate as the evaporator can boil off. I know a 4x40 would easily do it but I think i would be lacking permeate to flush a membrane of that size. I currently have a 2x400 gpd ro with an aquatech. I do have 4 400gpd membranes and housings but only run two at a time as the pump really can't feed 4 of them imo. Suggestions?

[DRoseum]

I just went to 100 taps on 3/16 vacuum and built an RO using 5 of the 400 gpd membranes in 3012 housings using a coronwater typ-8900 pump. I loved it. Worked awesome.
https://youtu.be/9_Eq_sq6Tp0
I previously had the aquatec 8852 with 3 of those membranes. This doubled the speed and I was taking it from 1.25 - 1.5% to 7.5% or 8% in a single pass. Averaged 140 gallons of sap daily to run thru this and boil on a 20 x 42 rig. In future I might replace the 400 gpd membranes when they eventually go bad with 600 gpd ones that fit the 3012 housings to speed it up more.

Also, aquatec just started making a higher flow pump (5300 series). Specs look good but its not continuous duty (major negative). Also, aquatec doesn't sell direct to consumers and none of their distributors had it. Still can't find a place to buy it.

http://www.aquatec.com/documents/downloads/5300%20Series%2024VDC%206.00%20LPM.pdf

Lastly, you could also add another pump in a parallel set up to double flow rate at the same pressure. You could do that with another aquatec or 2 of the coronwater pumps. Although I haven't seen this used in DIY RO units, it is a common approach to increasing flow rate at the same pressure. This is different than a low pressure feed pump in series with a high pressure pump on bigger RO units. It is best to use identical pumps in a parallel set up and you will most likely need to use larger tubing on the intake and throughout the system (only 1/4" on final concentrate exit and 1/2" for intake/feed)

https://www.google.com/amp/s/www.engineeringtoolbox.com/amp/pumps-parallel-serial-d_636.html

[eustis22]

I have two new 400 GPD membranes. What is the flushing procedure for new membranes out of the box? I do not have permeate but did buy a carbon filter so I can use my tapwater.

[DRoseum]

Flush new carbon block filter first for 15 mins and then hook up to membranes and flush with no back pressure for 1 -2 hrs.

[DrTimPerkins]

Flush new carbon block filter first for 15 mins and then hook up to membranes and flush with no back pressure for 1 -2 hrs.

A standard sediment filter is more appropriate. Use of a carbon filter with sap or syrup is actually illegal.

[DRoseum]

I should have been more specific... this is for initial flushing of new membranes with CITY water which contains chlorine that needs to be removed to prevent membrane damage. The carbon block filter is only used in this stage and then removed and replaced with a regular sediment filter when actually processing sap.

Is that illegal?


A standard sediment filter is more appropriate. Use of a carbon filter with sap or syrup is actually illegal.

[eustis22]

my apologies, I should have been clearer...I will fill a tank with tap water run thru a carbon block filter, then run THAT thru the membranes.

[eustis22]

Well, sadly, after performing very well running de-chlorinated city water thru the RO for a few hours to flush my new membranes, my brand new Coronwater pump didn't even turn on when I plugged it in to start processing my sap. I've sent a message to the seller but I do not expect any satisfaction (china, right?). I will switch back to the aquatec and hope that has enough oomph to get thru the membranes.

[82cabby]

Any chance it’s the power supply? (I ask optimistically…?)

[darkmachine]

easy way to check, throw a multimeter on it and see what the voltage reads. I'm not familiar with aquatec or similar pumps, do they have overload protection, like a built in breaker you can reset?

[eustis22]

I can put a multimeter on the power supply, I guess. Not sure how I would check the pump itself. I do not see any thermal switches on the pump.

[DRoseum]

Definitely check power supply. Others have had that be the issue. I've run these pumps for 6+ hours a day for 3 seasons with thousands of gallons of sap and haven't had one fail.....yet...knock on wood. Lol

[82cabby]

Another thought, check the breaker and GFCI. My GFCI tripped today and I was panicking wondering why the RO had stopped after checking the breaker and finding it OK. Took a bit to remember the GFCI.

I do have to say though, these Coronwater pumps sure run hot. This week was my first trial with mine and at 110-115 psi it’s really hot to the touch. Moves a lot of sap though, that’s for sure.

[eustis22]

yeah it's not the breaker of gfci as the pump doesn't work on various plugs. Broke down and ordered a new power cord but it won't get here until 3/12. In the meantime, if I need an alternative (I dunno I want to order another coronawater) for a 2X400GPD membrane system with no recirc?