RO/DI vibrating & can anyone help?

FastUno · #1 03/18/2007, 10:25 PM

I bought one of thsoe RO/DI units from ebay from FilterDirect. WaterGeneral I believe is the manufacturer.

It's barely 6mo old & has gradually stopped producing water. Mind you that I had one of these before that worked very well. This one has never qute produced the same amount of water as my previous unit.

I have changed out the valve coming out from the membrane, since it seems that too much force was needed to force out water. I also replaced the membrane just in case. Still over time it gradually stops producing water. It often vibrates on it's own as well.

Has anyone experienced this?

Colin · #2 03/19/2007, 07:37 AM

Maybe air trapped in it somewhere? Do you have a shutoff valve on it? Those can be a culprit. You can try turning the thing on it's side while running to see if you can dislodge any trapped air bubbles.

Good luck,

--Colin

FastUno · #3 03/19/2007, 07:37 PM

I tried turning it on it's side & shaking it upside down.
Last I did that, replaced 1 valve off the membrane chamber & the membrane itself and still the same result.

It puts out water, but not nearly as much as my original/older RODI & over time barely produces anything.

AZDesertRat · #4 03/19/2007, 08:34 PM

Explain what you mean by "I have changed out the valve coming out from the membrane, since it seems that too much force was needed to force out water."
Have you calcualated the waste ratio? What is your water temperature, pressure and incoming TDS? What membrane did you replace it with and what size flow restrictor does it have? What prefilter and carbon does it have and have they been replaced at 6 months like recommended?

FastUno · #5 03/20/2007, 07:12 PM

The system was barely used & out of the box it barely produced water. I replaced with filters provided by the same CO. that sold me the filter.

Don't know the name of it, but there are 2 outputs out of the Membrane housing. One that direct flow to the drain & another that continues the flow to the holding tank & DI unit. When I removed this valve it looks like it opens up when pressure is applied from the inside membrane. When I blow in the valve I could not get it to open. When I blow in a new valve, it opens up with some pressure.

I have barely used the new filters that I replaced with. With my previous filter, from the same CO, I had it for more than 2 years on & it still produced water.

AZDesertRat · #6 03/20/2007, 07:34 PM

Sounds like you are referring to either a check valve or a flow restrictor? The flow restrictor goes in the waste line to the sink drain and the check valve goes on the product or good water line with the arrow pointing away from the membrane. Sounds like you may have something plumbed wrong or you may have the wrong flow restrictor. How much waste are you getting compared to the good? It should be 4:1 or 4 gallons of waste for every 1 gallon of good. Time the flow with a measuring cup or graduated pitcher and see where you are at. If the waste is too high you don't have sufficient pressure to produce good water.

FastUno · #7 03/20/2007, 08:20 PM

I just tried a little experiment. I get the following:

-Water output directly after 3 canister filters is a fast stream.
-Water after the Membrane & that 4-way diverter I only get 1 drop/sec, at best 2 drops/sec.
-Water going to drain is a steady sharp/light jet. Much more water coming out of waste. More like 10:1.

Does the water out of waste ever stop, when the filter is full of water & the tank full of water? I tried blocking the RO output (the water dripping every second) & the waste water did not stop.

AZDesertRat · #8 03/20/2007, 08:30 PM

Do you have a flush valve or adjustable waste valve? The 4 way thing you are speaking of is probably the auto shutoff valve. I think you have the wrong size flow restrictor if your waste ratio is that high. With 10:1 you will never make much water. It needs to be 4:1. I don't know who you are dealing with but sounds like you need a new RO supplier that will take care of you. E-Bay vendors won't do this as it cuts into their profits. Reef Central RO suppliers are hobbyists themselves so they understand your needs. E bay may be great for some stuff but not RO/DI systems.

FastUno · #9 03/20/2007, 08:43 PM

THis is the unit I have:
http://filterdirect.com/catalog/prod...products_id=30

The flow restrictor says 600 on it.

AZDesertRat · #10 03/20/2007, 08:53 PM

Unfortunately that is one of the lowest quality RO units on the market, no offense to you. They are horrible.
The flow restrictor should be the right size. Do you have a TDS meter and have you tested the tap water TDS, RO only TDS and RO/DI TDS to determine efficiency? You really need to do so.
It would not surprise me at all if you have a defective part somewhere. Those units are mass produced in China and sold by the boatload to unsuspecting people who are unaware of the differences between a good and bad unit. Cheap is not good. There are good values out there but they start at $149 for a reef quality unit. I hope the vendor can help you further since they know their system but I would not hold my breath, I really try to steer people clear of those units and that vendor for obvious reasons. Sorry.

FastUno · #11 03/20/2007, 08:56 PM

At this point I am willing to buy a new one? WHat do you recommend, I need something with a 5g holding tank, like this same one on ebay (same supplier).

http://cgi.ebay.com/ws/eBayISAPI.dll...3270&rd=1&rd=1

AZDesertRat · #12 03/20/2007, 09:12 PM

www.buckeyefieldsupply.com
www.thefilterguys.biz
www.purelyh2o.com
www.spectrapure.com
All sell good reef quality units with drinking water kits. Get a reef system and add the drinking kit and not a drinking water unit and add a DI, there is a big difference in most cases. All sell units with true vertical DI filters and true RO membranes not nano filters like some e bay units.

sjm817 · #13 03/20/2007, 09:38 PM

Here is a diagram that thefilterguys have on their website. Maybe that will help.

jdieck · #14 03/20/2007, 09:48 PM

By your description it also seems the Auto Shut Off valve (ASOV) might be connected backwards (What you call the 4 way diverter) Check the above diagram and check all your connections. Pay special attention to the conections marked IN and OUT on the ASOV valve as well as the location of the check valve and flow restrictor.

By the way if you buy a new one, do not get 100 gpd membrane. 75 gpd membranes have higher performance and will save you money in DI cartridge replacement.

FastUno · #15 03/22/2007, 08:27 PM

That is the way it's hooked up. The Auto Shut off valve is the source of the vibration from time to time. When it vibrates I simply turn on the faucet for a few seconds & it tends to go away. At least for a little while.

I am still producing barely any RO or DI water. At best I can get a gallon, sometimes not even. More like 1/2 gal at times.

jdieck · #16 03/22/2007, 08:32 PM

See below

jdieck · #17 03/22/2007, 08:37 PM

Before doing anything check that the flow restrictor is set to restrict and not to backflush. (The lever of the valve should not be on the flow position, it should be perpendicular to the line, in the normal position)

If the flush valve is closed and your tap pressure is 50 psi or higher then I will suggest replacing the ASOV, it might not be opening properly. To cvheck this remove the ASOV, connect the output of the carbon filter directly to the inlet of the membrane, and the product line from the membrane directly to the DI cartridge. See if that increases production. Also check that the direction of the check valve in between the membrane and the DI cartridge is set properly.
Another test to check if the restrictor is the right size is to install a small valve in the waste line and partially close it, if a ration of 4 of waste to 1 of product is possible with the valve then the restrictor is not the proper size or is not adjusted properly.

FastUno · #18 03/22/2007, 08:49 PM

I dont have a lever on the flow restrictor & there is an arrow that shows the right direction, so I think that is correct?

I decided to replace my old unit (filters were getting old) with this newer one & gave my old one away quite some time ago. The old one worked fine & was fine with water pressure...so this one should be too?

I am beginning to think it's a defective ASOV. I will have to try the removal of the ASOV test some other day, since I dont want any leaks over night.

Thanks

FastUno · #19 03/22/2007, 09:02 PM

Interesting....off the filterdirect site:

Vibrating noise or very loud high pitch noise
1. From the auto shut-off valve
1. If the noise is too unbearable, shut-off valve should be replaced.

jdieck · #20 03/22/2007, 09:16 PM

Quote:

Originally posted by FastUno
Interesting....off the filterdirect site:

Vibrating noise or very loud high pitch noise
1. From the auto shut-off valve
1. If the noise is too unbearable, shut-off valve should be replaced.

Yes ASOVS tend to do thatbecause of bad quality or when the inlet pressure is too low.
The ASOV valve should positively shut off when the pressure on the product line reaches 85% of the pressure of the inlet line.