RODI Help

Echomsp · Mar 18, 2021

So my RODI had two membranes. After some reading, I've learned that my tap water's TDS (500-600) is too high for a dual membrane setup.

I've purchased a new RO membrane and a new flow restrictor to go along. I'm rerouting lines to remove the second membrane and based on my research, it appears my unit was running differently than those I've seen.

The waste line was routed through the high pressure side of the ASO and the product water routed through the low pressure side. The pressure switch for the booster pump was installed on the waste line coming out of the ASO.

It seems as though the line coming from the carbon filter should be routed through the high pressure side and out to the RO membrane. The product water going through the low pressure side as installed previously.

The pressure switch for the booster pump should be installed just upstream of the float valve for my RO reservoir, right?

I installed the ASO and booster switch in this manner and it appears I broke everything. The ASO is not shutting the supply to the membrane off and the booster pump was not running. After sitting off for a few minutes, pressure starts to build and then the booster pumps kicks on. Before I could shut the tap water supply valve off, I watched the pressure build to peg out all my pressure gauges. Fortunately, none of the seals blew.

What am I doing wrong? Any help is appreciated!

Biglew11 · Mar 18, 2021

here's a diagram of how the lines should be ran and a video how to install the a.s.o. valve.
I'll have to look when i get home but i think i put the auto shutoff between the last carbon block and the booster pump.

Echomsp · Mar 18, 2021

Here is my attempt at a schematic of my setup. I'm having multiple problems with it. The ASO is not shutting off the line into the RO when the float valve is closed and pressure builds. The float switch is not turning on the booster pump with low pressure, but as pressure builds it turns on the booster and pressure sky rockets.

Yes, I know I have a lot of filters, but I believe my awful tap water is causing phosphate problems with my tank. I'm feeding sparingly every other day, and pulling piles of GHA from the tank. I'm getting 0 TDS reading coming out of both DI filters, but still able to measure phosphate in my filtered water using Hanna Checker.

Open to any advice to improve the water quality.

Echomsp · Mar 19, 2021

I bought a new ASO, but still waiting on delivery. I adjusted the booster pump as much as possible, but still boosting pressure to 120 psi. Any idea what else I can try?

Echomsp · Mar 26, 2021

Installed the new ASO and removed pressure switch for now. When I close the valve downstream of the last DI, the pressure gauge on the RO will fluctuate between 40 and 60 psi. I can hear water moving through the drain line which seems as though the ASO is not cutting the water supply off. Any idea what I'm doing wrong?

Biglew11 · Mar 27, 2021

without the pressure cut off switch the booster pump should still be running. if it is, and if it's before the aso it may be over powering the aso. you should put the pressure switch back in.

Echomsp said:
The float switch is not turning on the booster pump with low pressure, but as pressure builds it turns on the booster and pressure sky rockets.

just read this, some switches have two sets of contacts, labeled n.o. n.c. (normally open normally closed). if your has two connectors you want to use the n.c. and the common terminals. when pressure builds it will open the contacts and turn off the pump.

Echomsp · Mar 27, 2021

Without the pressure switch, there is no power to the booster pump. The ASO is not cutting the supply off with just the tap water pressure of about 45 psi.

I'll check the contacts on the switch, but right now I'm just trying to get the ASO to cut the supply off when pressure builds on the outlet.

Biglew11 · Mar 27, 2021

double check the hose connections on the aso. I don't think direction maters, but there is a high pressure side that gets the valve to shut off. the side without screw heads should connect to the line coming out of the last carbon block. check valve on the product line, then into the aso (side with screw heads).

when the float close it creates high pressure in the product water side of the ro membrane. the high pressure here creates enough back pressure to close the a.s.o. shutting off the supply water. the check valve is supposed to keep the aso pressurized and turned off. #8 in this image is the check valve. mine is a separate straight style check valve that goes inline.