RO water drip rate slow

Spar · 03/03/2013, 03:53 PM

I have a 5-stage RO/DI unit with 150gpd membrane. It has recently become very slow dripping both on the RO/DI output and the waste line. I am getting 60psi, which is what I normally get. I switched out my sediment filter yesterday but that didn't help. I switched out my RO membrane about a year ago.

What is the most likely cause of this slow down?

hazey62 · 03/03/2013, 03:56 PM

have you tried to back flush for a while to see if that helps?

Spar · 03/03/2013, 04:41 PM

I did about 5g's just now, and it did help a bit. Still slower than I remember, but I can live with the current flow rate.

Thanks for that tip!

mr.maroonsalty · 03/03/2013, 05:01 PM

What's the temp at your plant? My system is in an unheated basement and I'm getting about 25 gallons a day to my upstairs display; Its making for an agonizing fill, fortunately, I still have other things to finish on my build.

mr.maroonsalty · 03/03/2013, 05:02 PM

Forget it ic you're in TX

Breadman03 · 03/03/2013, 05:10 PM

Could the carbon block be clogged?

Buckeye Hydro · 03/05/2013, 07:16 AM

Quote:

Originally Posted by Spar

I am getting 60psi, which is what I normally get.

Where is the pressure gauge in the system? Is it
1) before your entire system, or is it
2) after your prefilters (prefilters=all the filters that touch the feedwater before it reaches the membrane) and just before the membrane?

Russ

Spar · 03/05/2013, 07:41 PM

Quote:

Originally Posted by BuckeyeFS

Where is the pressure gauge in the system? Is it
1) before your entire system, or is it
2) after your prefilters (prefilters=all the filters that touch the feedwater before it reaches the membrane) and just before the membrane?

Russ

The pressure gauge is after the pre-filters (sediment, carbon and then chloramine) but before the membrane. And I said 60psi before, but it is closer to 80psi. I use a booster pump on the unit to give me the nice pressure.

I changed out all the pre-filter items and still am getting poor performance. I also made sure my DI containers aren't clogged, which they aren't.

The water goes into the DI containers very slowly, and the only thing in between the two is the RO Membrane, so have to assume now that is what the issue is. I ordered a new one and get it on Thursday, shall see then! Good thing I made enough water to last me a long time before this thing crashed!

Buckeye Hydro · 03/06/2013, 05:04 AM

Also make sure you didn't accidentally install the DI cartridge upside down - the black rubber washer should be on the top.

Russ

Spar · 03/08/2013, 07:47 AM

Was the RO Membrane. Switched it out last night and had 50g's made by morning!

Not sure how it only lasted 1 year, but I do go through a ton of water with my big tank and 2 QT's. Guess I will just make it a yearly thing to switch it out.

Buckeye Hydro · 03/09/2013, 12:00 PM

If you have really had water that is depositing scale in the membrane and clogging it quickly, if you can, feed the membrane softened water, and make sure you have at least a 4 to 1 ratio of waste water to purified water.

Russ

Spar · 03/09/2013, 12:58 PM

Quote:

Originally Posted by BuckeyeFS

If you have really had water that is depositing scale in the membrane and clogging it quickly, if you can, feed the membrane softened water, and make sure you have at least a 4 to 1 ratio of waste water to purified water.

Russ

Our water is actually really soft here. 250 TDS right out of the tap. We have Chloramine but I use a Chloramine remover filter pre-membrane.

The instructions for my RO Unit says to have a 1:1 RO:Waste ratio given it uses a Booster pump. Never questioned it, but wondering what others with a Booster pump do ratio-wise?

Only thing odd with my unit now is that the pre-DI TDS is 4 and so is the post-DI water. Like the DI isn't doing anything. But it is new DI media.

Buckeye Hydro · 03/09/2013, 01:46 PM

Hmm. 250 ppm tap water doesn't equate to soft water.

A 1:1 ratio would be why you scaled your membrane. Should be 4:1. Regardless of your line pressure or boosted water pressure.

Russ

Spar · 03/09/2013, 05:19 PM

Quote:

Originally Posted by BuckeyeFS

Hmm. 250 ppm tap water doesn't equate to soft water.

A 1:1 ratio would be why you scaled your membrane. Should be 4:1. Regardless of your line pressure or boosted water pressure.

Russ

Googled it and go figure you are right

Not sure why I always thought 250 was low. Guess I had heard of people with wells or in other areas with 450ppm+.

Buckeye Hydro · 03/09/2013, 05:41 PM

Yep. Remember that the TDS reading of your tap water, is related to, but not the same as hardness.

We have customers with Tap water TDS from less than 20 to over 1200 - your tds level, 250, is pretty darn common.

Russ

03/03/2013, 03:53 PM	#1
Spar Registered Member Join Date: Mar 2006 Location: Plano, TX Posts: 2,517	RO water drip rate slow I have a 5-stage RO/DI unit with 150gpd membrane. It has recently become very slow dripping both on the RO/DI output and the waste line. I am getting 60psi, which is what I normally get. I switched out my sediment filter yesterday but that didn't help. I switched out my RO membrane about a year ago. What is the most likely cause of this slow down? __________________ 450g Mixed SPS/LPS Reef (MH/T5/VHO)

03/03/2013, 04:41 PM	#3
Spar Registered Member Join Date: Mar 2006 Location: Plano, TX Posts: 2,517	I did about 5g's just now, and it did help a bit. Still slower than I remember, but I can live with the current flow rate. Thanks for that tip! __________________ 450g Mixed SPS/LPS Reef (MH/T5/VHO)

03/03/2013, 05:01 PM	#4
mr.maroonsalty Registered Member Join Date: Jan 2003 Location: upstateny Posts: 2,504	What's the temp at your plant? My system is in an unheated basement and I'm getting about 25 gallons a day to my upstairs display; Its making for an agonizing fill, fortunately, I still have other things to finish on my build. __________________ Back from the dead! Current Tank Info: 140 dt reef

03/03/2013, 05:02 PM	#5
mr.maroonsalty Registered Member Join Date: Jan 2003 Location: upstateny Posts: 2,504	Forget it ic you're in TX __________________ Back from the dead! Current Tank Info: 140 dt reef

03/08/2013, 07:47 AM	#10
Spar Registered Member Join Date: Mar 2006 Location: Plano, TX Posts: 2,517	Was the RO Membrane. Switched it out last night and had 50g's made by morning! Not sure how it only lasted 1 year, but I do go through a ton of water with my big tank and 2 QT's. Guess I will just make it a yearly thing to switch it out. __________________ 450g Mixed SPS/LPS Reef (MH/T5/VHO)

03/03/2013, 03:56 PM	#2
hazey62 Registered Member Join Date: Feb 2013 Location: Ontario, Canada Posts: 129	have you tried to back flush for a while to see if that helps?

03/03/2013, 05:10 PM	#6
Breadman03 New Old School Join Date: Feb 2012 Location: Luzerne County, PA Posts: 3,293	Could the carbon block be clogged?

03/06/2013, 05:04 AM	#9
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Also make sure you didn't accidentally install the DI cartridge upside down - the black rubber washer should be on the top. Russ

03/09/2013, 12:00 PM	#11
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	If you have really had water that is depositing scale in the membrane and clogging it quickly, if you can, feed the membrane softened water, and make sure you have at least a 4 to 1 ratio of waste water to purified water. Russ

03/09/2013, 01:46 PM	#13
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Hmm. 250 ppm tap water doesn't equate to soft water. A 1:1 ratio would be why you scaled your membrane. Should be 4:1. Regardless of your line pressure or boosted water pressure. Russ

03/09/2013, 05:41 PM	#15
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Yep. Remember that the TDS reading of your tap water, is related to, but not the same as hardness. We have customers with Tap water TDS from less than 20 to over 1200 - your tds level, 250, is pretty darn common. Russ