[Paul H]

hi all

well just rigged up my garage RO/DI systems 

its only a 200 gpd ( i inherted it ) with my other gear..

So set up flushed through...

flow rate was about 90/10 ... in favour of waste

so drain off fit DI... 0ppm so happy

however production rate is at a dribble.. .. and i mean a dribble... some 1.5 hours later only 1/2 25ltr barrel produced..

1. Am i over expecting?
2. Is there something wrong or something i should / could do (i know about boosters etc..) but i feel the presuure is good from my tap so feel i should at least have a better production flow
3. Change filters / membranes maybe?

or is this the best i can expect from this unit

cos at this rate over a 24hour period this will give me 200litres.. (enough at the mo seeing as i'm getting started )

I'm just thinking something is wrong somewhere

can any one help or advise

thanks

[gto]

flush valve is open, look for a little tap turn it the other way.
you should then have a slower waste and faster pure, its only a 200gpd so don't expect a litre a minuit.

my old 200gpd was 4:1 waste to good, and made 12l an hour. so go ruffly by that

[combat1]

my 200gpd unit produces makes 200 litres in around 4 hours with a booster pump fitted, bit longer when the resin needs changing or the filters are coming due for a change.

[gto]

i doubt your is a 200gpd with that production rate.

i have had a 200gpd, a 450gpd and a 650pgd.

and 200l in 4 hours is very high for a 200gpd

[Paul H]

flush valve is open, look for a little tap turn it the other way.
you should then have a slower waste and faster pure, its only a 200gpd so don't expect a litre a minuit.

my old 200gpd was 4:1 waste to good, and made 12l an hour. so go ruffly by that

Yeah i opened the valve to flow to flush through... then back the other way (flow off)

at the mo ive timed 12ltr per 1.5 hours...

filter / membrane change help??

[bumper]

takes   hour  half  to fill 2Ll drum and i some times to foget to turn tap off so when i get up in morning ive wasted loads of  pure water 

[Paul H]

takes   hour  half  to fill 2Ll drum and i some times to foget to turn tap off so when i get up in morning ive wasted loads of  pure water 

so i'm guessing that the system is working fine then as 25lts is the 3 hour mark??

[gto]

unfortunatly yes thats about right, a booster pump will help a bit.
but as you say you inherited it, you may as well run it for a while then buy a brand new better one.

[johnny bravo]

i had same issues, put me off and sold it with a pole,    just got a 3oo RO in a job lot,   with a pump added   its filling a 25 litre drum up in 35 min.     previously 3 hours with my 200 RO without a pump.     pay £48 - £64  for pump on ebay .     see the difference imediatelly,  puts a smile on your face.    pump needed defo.

[dazmond]

whats your tds from the tap paul?mine around 35-45 so DI ONLY for me.its so easy and quick to purify my water for the next days work!!

it takes around an hour to fill my 350L tank.i feel sorry for you lot with hard water.it must be a right royal pain in the a*** faffing about with an RO and softeners.

[Ian Lancaster]

flow rate was about 90/10 ... in favour of waste

 

Ouch.  I hope you're not on a meter.  9:1 is way too high, it means nearly all the supply water is going down the drain and the higher the ratio the less pressure there is on the surface of the membrane.

It should be about 3:1

Maybe your restrictor valve is faulty.  If you fit a quarter turn valve in the waste line, you can set the ratio manually.  All you need then is a bypass in the waste with another quarter turn valve so you can open the line for flushing.

Much more reliable than pre-set restrictors

[dd]

What is your water pressure? You need at least 50psi for your RO to work efficiently.

I suspect you need new membranes and possibly a booster pump if you have low mains pressure. I would also change the pre-filters while you are at it. If the membranes have dried out they will be damaged. Also they could  be glogged up with limescale which will slow production.

What is the tds of water from RO (before it gets to DI)?

[Paul H]

whats your tds from the tap paul?mine around 35-45 so DI ONLY for me.its so easy and quick to purify my water for the next days work!!

it takes around an hour to fill my 350L tank.i feel sorry for you lot with hard water.it must be a right royal pain in the a*** faffing about with an RO and softeners.

tds just over 200

[Paul H]

What is your water pressure? You need at least 50psi for your RO to work efficiently.

I suspect you need new membranes and possibly a booster pump if you have low mains pressure. I would also change the pre-filters while you are at it. If the membranes have dried out they will be damaged. Also they could  be glogged up with limescale which will slow production.

What is the tds of water from RO (before it gets to DI)?

tds from RO was 5 i think....although i cant remember but i know it was quite low around there.. so rigged up D/I .. 0 after that... kept checking every so often too and it remained at 0 throught the 50 litres ive just produced..

yeah i have new filters think ill fit them and see how that goes.. then look at membranes.. if no improvement

[Avo]

Thats way to slow mate for this line of work, just sell it to someone with marine fish on eBay. I bought a secondhand merlin from a very nice guy on here few weeks ago and doing 75 litres an hour without booster pump, I'm well happy with it!!!

[dd]

Water purity is OK. My guess is the membranes are clogged up with limescale and need replacing.

[Paul H]

Water purity is OK. My guess is the membranes are clogged up with limescale and need replacing.

cheers .. ive got filters to replace so trying that next .. will have to order membranes..

got 50 litres to get going to pratice my system and set up on my house  over the weekend..

last weekend was about practising my trad skilss on my house ... what a difference a wekk makes!

thanks for help

[Spruce]

Water purity is OK. My guess is the membranes are clogged up with limescale and need replacing.

cheers .. ive got filters to replace so trying that next .. will have to order membranes..

got 50 litres to get going to pratice my system and set up on my house  over the weekend..

last weekend was about practising my trad skilss on my house ... what a difference a wekk makes!

thanks for help

Hi Paul

Do as Ian Lancaster has advised first before you do anything else. If your water to waste ratio is 9:1 then the R/O will never produce much pure. Ours works on a ratio of about 3:1 which will give a good result efficiency wise. We use a restrictor.

Replacing the membranes could be a waste of money without solving the pure to waste ratio first.

Spruce

[dd]

I experienced a similar problem with my 300gpd RO. Water production slowed although the product water was still 004 tds and the waste went up.

This was immediately rectified when I changed the membranes. Waste went down and pure production increased. It was caused by the membranes getting clogged up with limescale. Conversely if they get clogged with chlorine the tds will rise but if they are clogged with limescale the tds remains low but the production rate slows and waste increase.

[Paul H]

Water purity is OK. My guess is the membranes are clogged up with limescale and need replacing.

cheers .. ive got filters to replace so trying that next .. will have to order membranes..

got 50 litres to get going to pratice my system and set up on my house  over the weekend..

last weekend was about practising my trad skilss on my house ... what a difference a wekk makes!

thanks for help

Hi Paul

Do as Ian Lancaster has advised first before you do anything else. If your water to waste ratio is 9:1 then the R/O will never produce much pure. Ours works on a ratio of about 3:1 which will give a good result efficiency wise. We use a restrictor.

Replacing the membranes could be a waste of money without solving the pure to waste ratio first.

Spruce

talk me through this restrictor valve process... in idiot format please ..