Typical pressure loss across RODI pre-filters?

[Potatohead]

I recently upgraded my RODI unit. It's an AquaFX Barracuda 100 four stage. I have always had a pressure gauge on the feed line to my RODI unit which measures from 60-70 psi depending on time of day and water demand in the neighbourhood. This is consistent with the reading from the water gauge at the pressure limiter coming into the house (few psi lower). The AquaFX has another gauge between the carbon block and membrane and this consistently reads about 18 psi lower than my gauge on the feed line. I thought that can't be right and bought another gauge, same thing.

My water is only 14 TDS out of the tap and I have run maybe 250 gallons through this unit (waste included) this far. Is this type of pressure loss normal? I'm pretty sure they're both 1 micron filters (carbon might be 2), there's no way they're plugged already.

Thanks

 

[Big G]

Yeah, that's about the same range on my BRS Four Stage unit connected to my well's pressure tank. Pressure tank reads 60-62; RODI reads 45-50

 

[Potatohead]

Ok, I guess it's normal then. Thank you.

 

[Potatohead]

So this whole thing has been really weird.

Over the last few weeks I just kept losing pressure into the membrane. I was up to 30 psi drop yesterday. I said this just can't be right so after swapping some things around I determined my carbon block was half plugged. I have no idea why the carbon would get clogged and not the sediment filter, it just makes no sense. The sediment is 1 micron and the carbon 2 micron. I hope it was just defective or something because going through a block every 80 gallons of product water just doesn't make any sense especially considering our tap water is crazy clean and very little chlorine.

The LFS only had 5 micron carbon blocks, I would have preferred smaller but with the water we have it probably doesn't make much difference. I guess all I can do is monitor pressure loss on this new block. Now my pressure loss is only 2-4 psi.

 

[Big G]

Your local plumbing supply also should have RO/DI filters, etc. When comparing products for quality it is difficult to actually "see" the differences. I try to stay away from overseas RO/DI filters, etc. Sediment filters you can actually see the thickness and density difference. But carbon, etc. it's tough to know if you are getting the real thing or just some cheap imitation. Yikes!

 

[Potatohead]

Your local plumbing supply also should have RO/DI filters, etc. When comparing products for quality it is difficult to actually "see" the differences. I try to stay away from overseas RO/DI filters, etc. Sediment filters you can actually see the thickness and density difference. But carbon, etc. it's tough to know if you are getting the real thing or just some cheap imitation. Yikes!

The "bad" one was the one that came with the AquaFX unit, the new one is whatever comes in the Vertex Puratek unit. I'm not really one to buy the cheap stuff was in a bit of a bind. I will put it on the list for the next online order I make. I like the idea of the pleated sediment filters too, much more surface area.