Ro Unit

[smelly shelley]

Hi
I have a R O unit. But it only makes about 20L of water every other day, sometimes longer. The RO unit should make about 120L every 48 hours. Is the unit nackered or have i got to do something to the mains supply of water to the unit.I think my water pressure is about 2bar is that enough it work the unit?

 

[idlefingers]

There's quite a few factors which contribute to how fast RO is created.. water pressure (2 bar / 30 psi is normally enough but it could be better), temperature and the quality of the incoming water are the main things I think. Obviously you can't change the quality of the incoming water but if your cold water is really cold, you can fill a bucket with water and chuck a heater in then use a long piece of RO tubing coiled up inside the bucket so the water is heated a little before it enters the unit.

 

[Musho3210]

optimal is 80-100 PSI and 77-78 degree water, if you have both of those it should be producing near the amount that you bought (aka you bought a 75 gpd unit it should produce 75 gpd with those optimal settings) If its less that those optimal numbers then it will produce less water, if its more, it may damage the RO membrane by tearing it or melting it.

 

[AK77]

I'm not sure how many GPD my 6 stage RO unit is. I only muster 35 psi from mains pressure. I could probably get 3 x 25L containers done a day I'd guess. Not a huge amount, but I have 5 containers, which I keep filled and rotate the order. I do monthly water changes so there's no major rush where I'm concerned. Its much easier to store the water than wait around for buckets to fill up.

You can get the 25L containers from a number of places. I've seen them on ebay for a few quid each. Probably need washing out as most have been used to store cooking oils or other catering fluids, but once washed and cleaned, they are ideal.

 

[pengy666]

I just go wild on a weekend and fill my 205Ltr water butt in back garden when I've emptied it! it takes about that long to fill!

But I do turn RO unit off at night and and when I go out, And I have a 4 stage with DI unit and i got 35psi too!

 

[DarrenUnwin]

Hi

Temperature and source water pressure are usually the culpret, pressure being the more important one. The ROMAN manual recommends the unit I have (4 stage plus DI) as needing a minimum of 40 PSI for it to function correctly.

As for temperature, hard to say direct affect but I definately get more ro water in the summer months than winter.

Tip on water storage, have a trip down to you local home brew specialist, they have loads of different kit to help out. Also if you buy say 2 x 5 gallon brew bins to store or mix your salt water before the change, make sure you buy another spare 5 gallon bucket to siphon the exact amount of water out as your putting in, this way you dont have the problem of having to waste or mix extra water and salt at the end of the change when the tank water level isnt quite right.

Good luck.

One last thing, if you have used ptfe tape to help secure the tap seal to the mains, just check you havent got any stuck in the area when the joint is made as this can restrict flow.

 

[steelhealr]

Flow is largely dependent on the water pressure in your house. Here..in the US...pressure under 40-45 PSI usually leads to slow output. There are pumps you can buy that increase the pressure into the RO unit but, they are unwieldy IMO. SH

 

[SkiFletch]

There are pumps you can buy that increase the pressure into the RO unit but, they are unwieldy IMO. SH

And LOUD. Stupid gear pumps.