HM DM-1 dual inline TDS monitor help!

[Anovack]

I need some help on where to install the "in" probe on my spectra pure 90gpd RO/DI unit. I know the out probe is for my line giving me the final product I'm just confused on what line to snip after the ro unit.

Out is the right blue line. Is the inline supposed to go on the left blue line in the second pic or the black line in the first pic going into the ro unit? Appreciate the help!!!

 

[Sniperhank]

The blue out the top looks like it will be your final product from the pictures. Black almost always indicates waste water.

 

[Anovack]

In the second pic that blue line on the left connected to the ro membrane goes down to my di cartridge then from the di cartridge is my final product. Does that sound right? So my in probe I want between my membrane and di cartridge to know which one starts failing first. I believe.

Thanks for reply sniper

 

[Anovack]

That black line is going from my second sediment cartridge (middle) up to my membrane which then goes to the di cartridge it looks like

 

[Sniperhank]

In the second pic that blue line on the left connected to the ro membrane goes down to my di cartridge then from the di cartridge is my final product. Does that sound right? So my in probe I want between my membrane and di cartridge to know which one starts failing first. I believe.

Thanks for reply sniper

The TDS meter should be coming off of the di cartridge. You want to be measuring your final product's TDS.

 

[Anovack]

Sniper I got that part. It's a dual TDS meter so I have 2 probes. One is obviously off the di cartridge and just trying to figure out where to utilize the second probe. Below is a pic of the TDS meter

 

[jeffaquarius]

I would monitor the incoming and outgoing tds on my di cartridge. It will give you an idea the tds from ro and the final stage from di.

 

[Anovack]

Yup that's what I did...running .002 TDS before di and post is .000. Pretty happy with it. For having a run of the mill rodi unit and for only 25 bucks I this meter cost I can't complain knowing when to change different parts