Clean It Up

UK Window Cleaning Forum => Window Cleaning Forum => Topic started by: geefree on November 19, 2012, 09:04:26 pm

Title: Got a little R.O. problem
Post by: geefree on November 19, 2012, 09:04:26 pm
Hi, i have a 300 gpd ro-man...i have recently replaced all filters and membranes... but the pure water is producing much much slower.

I have flushed the membranes , and i also know the drop in temperature can affect production,

But its much milder tonight and the problem is still there.

Any suggestions are appreciated.

 ;)
Title: Re: Got a little R.O. problem
Post by: colin purewater on November 19, 2012, 09:31:30 pm
Did you turn the tap on ;)
Title: Re: Got a little R.O. problem
Post by: G Griffin on November 19, 2012, 09:34:03 pm
First thing to do, is do the title of this thread in your best Frank Spencer voice and you'll get a much better response.
Title: Re: Got a little R.O. problem
Post by: Tom White on November 19, 2012, 09:52:12 pm
Hi, i have a 300 gpd ro-man...i have recently replaced all filters and membranes... but the pure water is producing much much slower.

I have flushed the membranes , and i also know the drop in temperature can affect production,

But its much milder tonight and the problem is still there.

Any suggestions are appreciated.

 ;)

Check it's not on flush. 

And did you buy the correct RO membranes?  They may all look similar, but they're not all the same.  Some produce more waste and less pure than others.
Title: Re: Got a little R.O. problem
Post by: H2GoKent on November 20, 2012, 05:52:14 am
I have exactly the same problem, where did you get your replacement membranes from?
I'll have to check cos I can't remember, but I defo bought 3 of 100gpd ones.

My production has gone down from 20 litres an hour to 12! Nothing else has changed in my set up, and I've been doing this for 9 years so I'm normally pretty clued up.
Title: Re: Got a little R.O. problem
Post by: Spruce on November 20, 2012, 08:14:28 am
Just because the weather is warmer doesn't mean your r/o is going to perform better. Its the temperature of the water that counts and that doesn't fluctuate much in winter - it slowly gets colder as the winter progresses.

Over the years we have found that the r/o usually produces fine into the cold weather and starts to slow down in Dec when the tap water is very cold. It stays that way until well into June when we see a noticable increase in production rates.

The other thing to do is measure your waste water to pure ratio. We get an empty 2 litre milk container and fill it for a minute and mark/note the level. Then do the same for the pure.

With RoMan type filters you should have a 3 waste to 1 pure ratio. If you don't then you need to either adjust this on tap on the outlet or buy the correct restrictor for the membranes you have. RoMan sell them.

It is recommended that this inline restrictor be replace with every membrane change. If you have upgraded the membranes, ie 100 to 150 then you need to replace the restrictor.
Title: Re: Got a little R.O. problem
Post by: Spruce on November 20, 2012, 08:38:44 am
I have exactly the same problem, where did you get your replacement membranes from?
I'll have to check cos I can't remember, but I defo bought 3 of 100gpd ones.

My production has gone down from 20 litres an hour to 12! Nothing else has changed in my set up, and I've been doing this for 9 years so I'm normally pretty clued up.

If you have had the same setup without changing anything then there are only 2 viarables - water temperature and water pressure. The water temperature is cold now and it could be that the water board has reduced the water pressure into your area.

Changing the subject a little.

We upgraded our 75 GPD membranes to 150 GPD. They were  more expensive with a new restrictor as well, but they doubled our water production in both summer and winter - even with slower production rates in winter. We produced water into an IBC tank with a float switch connected to a solenoid valve. This meant that we didn't have to worry about the system as it switched the water to the r/o off when the IBC tank was full.

I can only describe that this upgrade was like a turbo diesel remap in performance for minimal cost.