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fishreef1
07/07/2010, 10:56 PM
Where is the best place to install an in line pressure guage on an RO/DI unit?

tannerd
07/07/2010, 11:20 PM
i have mine installed right after i tapped into my water off of my hot water heater 6 feet away from the ro/di unit. i dont know if that is right but it has been working for me.

Mike31154
07/07/2010, 11:23 PM
Two places. First, right at the input to monitor input pressure, second, immediately before the RO membrane. This way you can keep track of the pressure differential between the input and after your pre filters. This is the best way to keep track of when your pre filters are starting to clog or if there's a problem with the membrane.

Mike31154
07/07/2010, 11:29 PM
i have mine installed right after i tapped into my water off of my hot water heater 6 feet away from the ro/di unit. i dont know if that is right but it has been working for me.

Not sure tapping into the hot water system is a good idea for running a RO/DI unit. If you have a conventional hot water tank, I think you'll end up clogging your RO/DI unit quicker. If it's a tankless (on demand) hot water heater, you're probably ok.

Toddrtrex
07/08/2010, 12:00 AM
Tapping into the hot water heater (( besides the issue that Mike mentioned )) stands a good chance of ruining your RO membrane -- they are not designed for hot water.

Mine is before the RO membrane, and I use that as a guide to change the pre-filter/carbon. My pressure starts to drop before the normal 6 month change time.

fishreef1
07/08/2010, 12:13 AM
The monitoring of the prefilter part was what I was trying to remeber. Do you guys flush your membranes? If so how often? Thanks alot for the help!

fishreef1
07/08/2010, 12:20 AM
Also, do you run 2 TDS meters? 1 to monitor feed water and after DI and 1 for before and after membrane?

fishreef1
07/08/2010, 12:29 AM
i have mine installed right after i tapped into my water off of my hot water heater 6 feet away from the ro/di unit. i dont know if that is right but it has been working for me.

I thought you wanted feed water around 70 degrees for optimal water rejection ratios. I know when feed water temps get lower your rejection rate goes up. If you use hot water does rejection rate go down?

Toddrtrex
07/08/2010, 12:30 AM
To be honest, I have never flushed my system, and still get good results.

As for the TDS meter, I prefer hand held ones, so mine isn't installed.

fishreef1
07/08/2010, 10:00 AM
OK thanks for the help