Ro/di stuck at 40 psi

Mr Fishface

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For a while my rodi unit has been only able to get up to 40 psi. It takes forever to make a gallon of filtered water - about an hour. I thought this was due to my sink water pressure not being high enough but when I connected my unit to an outdoor hose I got the exact same result. I know the outside hose has much higher water pressure and it made me question if something is just wrong with my unit. I got a psi gauge and hooked it up to my sink - 55 psi right away.

I have an aquatic life 100 gpd system. I went and checked each filter to see if one was clogged. No change on the psi when I removed the sediment, carbon or DI filter. When I removed the ro membrane the system showed real low pressure. I suppose there’s nothing to give any resistance to allow pressure to build. What’s my next step here? Do I try to replace the ro membrane or does it seem like I need to replace the whole unit? How do I tell if something is wrong with the system itself?
 

Dread Pirate Dave

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For a while my rodi unit has been only able to get up to 40 psi. It takes forever to make a gallon of filtered water - about an hour. I thought this was due to my sink water pressure not being high enough but when I connected my unit to an outdoor hose I got the exact same result. I know the outside hose has much higher water pressure and it made me question if something is just wrong with my unit. I got a psi gauge and hooked it up to my sink - 55 psi right away.

I have an aquatic life 100 gpd system. I went and checked each filter to see if one was clogged. No change on the psi when I removed the sediment, carbon or DI filter. When I removed the ro membrane the system showed real low pressure. I suppose there’s nothing to give any resistance to allow pressure to build. What’s my next step here? Do I try to replace the ro membrane or does it seem like I need to replace the whole unit? How do I tell if something is wrong with the system itself?
A booter pump can help. I added a smart buddie to my system for increased output.

 

Patx

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For a while my rodi unit has been only able to get up to 40 psi. It takes forever to make a gallon of filtered water - about an hour. I thought this was due to my sink water pressure not being high enough but when I connected my unit to an outdoor hose I got the exact same result. I know the outside hose has much higher water pressure and it made me question if something is just wrong with my unit. I got a psi gauge and hooked it up to my sink - 55 psi right away.

I have an aquatic life 100 gpd system. I went and checked each filter to see if one was clogged. No change on the psi when I removed the sediment, carbon or DI filter. When I removed the ro membrane the system showed real low pressure. I suppose there’s nothing to give any resistance to allow pressure to build. What’s my next step here? Do I try to replace the ro membrane or does it seem like I need to replace the whole unit? How do I tell if something is wrong with the system itself?
What type of "restrictor" do you have ?
Manual ?

What is your rejection ratio ?
4:1 ?
 
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Mr Fishface

Mr Fishface

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For a while my rodi unit has been only able to get up to 40 psi. It takes forever to make a gallon of filtered water - about an hour. I thought this was due to my sink water pressure not being high enough but when I connected my unit to an outdoor hose I got the exact same result. I know the outside hose has much higher water pressure and it made me question if something is just wrong with my unit. I got a psi gauge and hooked it up to my sink - 55 psi right away.

I have an aquatic life 100 gpd system. I went and checked each filter to see if one was clogged. No change on the psi when I removed the sediment, carbon or DI filter. When I removed the ro membrane the system showed real low pressure. I suppose there’s nothing to give any resistance to allow pressure to build. What’s my next step here? Do I try to replace the ro membrane or does it seem like I need to replace the whole unit? How do I tell if something is wrong with the system itself?
What type of "restrictor" do you have ?
Manual ?

What is your rejection ratio ?
4:1 ?
Is the restricter the part of the unit that lets me control how much pressure goes into the unit? If so then yes, it is a manual. Not sure about the rejection ratio though.
 

Patx

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Maybe you have to much "waste" and not enough "good" (production).
So pressure can't build up...

Also do you flush (rince) your membrane "sometime" ?

The standard ratio waste/ro is 4:1
4 waste for 1 RO.

Start your unit.
Put the waste line in a container/bottle whatever.
And RO line in a other (same type)

Adjust the valve (restrictor) accordingly.
 

UncommonSense

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Is the restricter the part of the unit that lets me control how much pressure goes into the unit? If so then yes, it is a manual. Not sure about the rejection ratio though.
Here’s from the horses mouth!

IMG_7485.png
IMG_7487.png


IMG_7486.png


Given this info; your water pressure is low, but acceptable… I’m suspicious that this is another case of “let the apprentice assemble the unit” at the factory!

The auto-shutoff immediately came to mind, so I checked to see if this unit has one…

— ASO valves are preset to turn off the city water supply to your RODI automatically at 40PSI of RODI system pressure! If it is installed backwards, you’ll get barely a trickle of product water from your system, and 40PSI max pressure pre- RO membrane!
 

Buckeye Hydro

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A booter pump can help. I added a smart buddie to my system for increased output.

We advise customers to avoid these booster pumps in an enclosure. You'll want to be able to get to all the components easily, sooner or later.
 

Kodski

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We advise customers to avoid these booster pumps in an enclosure. You'll want to be able to get to all the components easily, sooner or later.
Its like two screws and the whole cover pops off. Very easy to service and it seems like all parts are easily replaceable. My Smart Buddy is the best thing I ever bought for my water filtration system, mine has been in service for 3 years without a single hiccup or issue to report.

The Smart Buddy is something I'd recommend to everyone, as it self flushes the RO unit every 24 hours of use or upon powering up, senses float valves and automatically turns on/off, keeps the water pressure consistent and I've seen a direct correlation to DI resin and Membrane usage due to this.
 

SeaDweller

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just a shot in the dark but... do you have one of those restrictor valves with a flush on it, and was it left open? a buddy of mine had super low pressure in his unit and almost 6-8 mos later figured out it was the flush valve being left open.

if not, i'd add a booster pump.
 

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