[C & S]

Just a slight problem I am having with my RO4040 setup I have made.

Obvisouly I need a pressure gague in it to fiddle about with the waste water ratio so I can see what PSI is the best for the system.

So..

a. Where to I put my gague? before membrane?  after it?

b. I am totally and utterly confused as where to get the gague from? I have one I tested my tap PSI with. Do I need some sort of T piece to add to the system?
If anybody has any pics or link I would br VERY appreciated as I'm stumped and cannot find anywhere :'

[Spruce]

Just a slight problem I am having with my RO4040 setup I have made.

Obvisouly I need a pressure gague in it to fiddle about with the waste water ratio so I can see what PSI is the best for the system.

So..

a. Where to I put my gague? before membrane?  after it?

b. I am totally and utterly confused as where to get the gague from? I have one I tested my tap PSI with. Do I need some sort of T piece to add to the system?
If anybody has any pics or link I would br VERY appreciated as I'm stumped and cannot find anywhere :'

Having pressure gauges isn't going to help you with adjusting your pure to waste ratio. For that you will need an inline tds meter.

We have a guage fitted each side of the prefilters. This helps me make a decision as to when to replace the sediment filter. Sometimes I need to replace the sediment filter every month and the carbon block every 3 months. (The water where we are can at times be heavily laden with sediment. The carbon block filter is replaced when the r/o has processed 78,000 liters of water - both pure and waste added together.  This is monitored with a water meter. We use 20" prefilters and the c/b filter is a Fiberdyne from Gardiners.)

Our tap water pressure is 50psi so when the filters are newly replaced, both gauges read about the same. As the sediment filter gets blocked with sediment the flow through the prefilters is restricted and this reflects on the water pressure guage after the prefilters. When the second guage reads 40 psi is when I replace the sediment filter - so a difference of 10 psi on the gauges.

I purchased 2 T pieces, 2 of the t's having 1/2" female thread and the 3rd 1/2" male thread. I got them from an automotive outlet on Ebay - not easy to find. But you could use 1/2" equal female t's with a male to male brass connector to screw into the filter housings.



Gauges
https://www.ebay.co.uk/itm/Air-Pressure-Gauges-2-Inch-Diameter-Bottom-Entry-ABS-and-Brass-up-to-3-8-Bsp/111172239817?hash=item19e261c1c9:m:mODLvSbA_0oSeFeE7SxcGWQ

This supplier will be able to help you with the t pieces you want as well as any reducers.

John Guest fittings from 1/2" female to 1/2" hose barb. See Gardiners.

[Simon Trapani]

I have a very similar setup to yours Spruce though with 10" pre-filtes & whilst I agree mostly with what you're saying I do think that the gauges as we both have them (before & after) do give a good idea over time of your pure to waste ratio.

I tend to begin producing pure late afternoon or late evening and I know roughly where my gauges are going to be at that time. It's been the same for years.

I have a mark on my waste gate valve to my 4040 that I turn to every time I produce as I know that is my sweet spot i.e lowest tds output before Di.

[Spruce]

I have a very similar setup to yours Spruce though with 10" pre-filtes & whilst I agree mostly with what you're saying I do think that the gauges as we both have them (before & after) do give a good idea over time of your pure to waste ratio.

I tend to begin producing pure late afternoon or late evening and I know roughly where my gauges are going to be at that time. It's been the same for years.

I have a mark on my waste gate valve to my 4040 that I turn to every time I produce as I know that is my sweet spot i.e lowest tds output before Di.

I've done that as well, but its been tuned to the inline tds meter. Interesting that you find that the gauges help you as well.