RO help for a newbie

Hi everyone, unfortunately it's a newbie looking for a bit more help. 

I've just gone fully wfp after years of upstairs with trolley wfp (purified by Di only) and downstairs trad. Now I have a 2nd hand xline 350l system with built in ro/di and auto flush. 

My water pressure seems quite low, unsure how much as unmeasured. Filling takes a long time and seems to be loads of waste compared to pure. So couple of questions 

• Is there a simple way to see how much waste per pure is being made? 
  
• Will a new ro filter speed up production or just make the water purer? 
  
• Is there anyway to close a valve on the waste as with a static ro system to reduce waste? 
  
• Will a booster pump help reduce the amount of waste being made or just speed up production? 
  
• I there a way to boost pressure without an expensive noisey pump? 
  

Sorry for the questions but I'm struggling to get get my head around ro. I've read loads, watched vids and still can't figure it out. 

Thank you so much for any input. 

Paul

Paul Symonds said:

Hi everyone, unfortunately it's a newbie looking for a bit more help. 

I've just gone fully wfp after years of upstairs with trolley wfp (purified by Di only) and downstairs trad. Now I have a 2nd hand xline 350l system with built in ro/di and auto flush. 

My water pressure seems quite low, unsure how much as unmeasured. Filling takes a long time and seems to be loads of waste compared to pure. So couple of questions 

• Is there a simple way to see how much waste per pure is being made? 
  
• Will a new ro filter speed up production or just make the water purer? 
  
• Is there anyway to close a valve on the waste as with a static ro system to reduce waste? 
  
• Will a booster pump help reduce the amount of waste being made or just speed up production? 
  
• I there a way to boost pressure without an expensive noisey pump? 
  

Sorry for the questions but I'm struggling to get get my head around ro. I've read loads, watched vids and still can't figure it out. 

Thank you so much for any input. 

Paul

Click to expand...

I know a little, others know more. But in order:

•get two measuring jugs, with measure lines on the side. Then start filling then at the same time, one from the waste the other with the pure. You can also time it and get a rough gauge of how much pure you can make in a hour etc. My R.O isn’t the most efficient, 3/1- 4/1 waste I’d say.

•your second question, do you mean a new whole R.O or just a new set of pre-filters? Or a new R.O. 

•don’t know the answer to the third question sorry haha

•booster pump will speed up both, waste and pure, so the faster the pure, the less time you’ll need the tap on. So ultimately less waste. I have a booster pump. It can at times triple my psi. 

•don’t think so. 

Sorry, meant a new ro membrane. Will it reduce waste, speed up production or just make the water more pure? Thanks 

Paul Symonds said:

Sorry, meant a new ro membrane. Will it reduce waste, speed up production or just make the water more pure? Thanks 

Click to expand...

Without knowing your water pressure then we will be guessing 

Paul Symonds said:

Hi everyone, unfortunately it's a newbie looking for a bit more help. 

I've just gone fully wfp after years of upstairs with trolley wfp (purified by Di only) and downstairs trad. Now I have a 2nd hand xline 350l system with built in ro/di and auto flush. 

My water pressure seems quite low, unsure how much as unmeasured. Filling takes a long time and seems to be loads of waste compared to pure. So couple of questions 

• Is there a simple way to see how much waste per pure is being made? 
  
• Will a new ro filter speed up production or just make the water purer? 
  
• Is there anyway to close a valve on the waste as with a static ro system to reduce waste? 
  
• Will a booster pump help reduce the amount of waste being made or just speed up production? 
  
• I there a way to boost pressure without an expensive noisey pump? 
  

Sorry for the questions but I'm struggling to get get my head around ro. I've read loads, watched vids and still can't figure it out. 

Thank you so much for any input. 

Paul

Click to expand...

First things first you need to measure your pressure. Surprised to see the X-Line systems don't have a pressure gauge built in at their prices! Pop down to your local tool station and grab one of these and measure the pressure at the tap, that should be somewhere near what its going through the system at;

https://www.toolstation.com/mains-water-pressure-test-gauge/p75711

Easiest way to measure pure to waste would be to get 2 jugs, let them fill up with waste and pure and adjust it until you get what you want. I thought this was pre set on an X-line system but I may have just read a previous post wrong.

Your 2 pre filters need to be changed regularly. You need to keep a track at least roughly of how much water you put through the RO and change them according to the manufacturer specifications. The pre filters are there to remove sediment and protect the membrane from damage. They don't necessarily decrease the TDS.

You should never set the RO beyond 50/50, ideally you want 55/45 waste to pure. Running beyond 50% pure will cause damage to the membrane. It doesn't appear from pictures on their website that X-line give you access to the gate valve. If this is correct it will more than likely be set to 60/40 waste to pure I imagine.

A booster pump will increase the pressure the RO is running at. Before you know if you need a booster pump you really need to know what pressure you're currently running at. If you're getting good pressure already the pump may be useful to you. If you aren't then it may be something you need. Increasing the pressure will reduce the TDS coming out of the membrane and will save you money on resin.

There are little things you can do to increase pressure but nothing makes the difference that a booster pump does. Make sure you have a good quality reinforced hose. Strong connections on it will help. Don't run the input hose through a hose reel... Outside of that not much you can do without a booster.

Paul Symonds said:

Hi everyone, unfortunately it's a newbie looking for a bit more help. 

I've just gone fully wfp after years of upstairs with trolley wfp (purified by Di only) and downstairs trad. Now I have a 2nd hand xline 350l system with built in ro/di and auto flush. 

My water pressure seems quite low, unsure how much as unmeasured. Filling takes a long time and seems to be loads of waste compared to pure. So couple of questions 

• Is there a simple way to see how much waste per pure is being made? 
  
• Will a new ro filter speed up production or just make the water purer? 
  
• Is there anyway to close a valve on the waste as with a static ro system to reduce waste? 
  
• Will a booster pump help reduce the amount of waste being made or just speed up production? 
  
• I there a way to boost pressure without an expensive noisey pump? 
  

Sorry for the questions but I'm struggling to get get my head around ro. I've read loads, watched vids and still can't figure it out. 

Thank you so much for any input. 

Paul

Click to expand...

Is there anyway to close a valve on the waste as with a static ro system to reduce waste? 

You must always have at least a 50/50 pure to waste ratio whilst producing water. You can't switch the waste off totally as it carries the impurities away that the r/o membrane removes whilst producing pure water. Our 4040 works best on a 45 to 55 pure to waste ratio when the tap water tds increases. (Ours fluctuates from 80 to 150ppm.)

When the tds is lower I can get away with 50/50. If you are in a hard water area then your waste to pure could be 60/40. Your ratio is dependant on your water pressure at the r/o, water temperature, and the composition of the dissolved minerals in your water. You need to adjust your waste and take test samples of your pure water to find the pure to waste ratio where your r/o produces the purest water. You have to wait for a few minutes to let the system settle down before you take a reading. I wait 5 minutes.

Our old 450gpd r/o had a preset inline restrictor which was 3 to 1.

Will a booster pump help reduce the amount of waste being made or just speed up production? 

It will speed up water production. On my system I have a gate valve on the waste which I tinker with or tweek to get the r/o's sweet spot. 

Is there a way to boost pressure without an expensive noisey pump? 

No is the short answer. However, if you are sending 5 liters of waste to the drain to produce 1 liter of pure then restricting the waste more could help. (Old Merlins ran on a 5 to 1 ratio.)

spruce said:

Is there anyway to close a valve on the waste as with a static ro system to reduce waste? 

You must always have at least a 50/50 pure to waste ratio whilst producing water. You can't switch the waste off totally as it carries the impurities away that the r/o membrane removes whilst producing pure water. Our 4040 works best on a 45 to 55 pure to waste ratio when the tap water tds increases. (Ours fluctuates from 80 to 150ppm.)

When the tds is lower I can get away with 50/50. If you are in a hard water area then your waste to pure could be 60/40. Your ratio is dependant on your water pressure at the r/o, water temperature, and the composition of the dissolved minerals in your water. You need to adjust your waste and take test samples of your pure water to find the pure to waste ratio where your r/o produces the purest water. You have to wait for a few minutes to let the system settle down before you take a reading. I wait 5 minutes.

Our old 450gpd r/o had a preset inline restrictor which was 3 to 1.

Will a booster pump help reduce the amount of waste being made or just speed up production? 

It will speed up water production. On my system I have a gate valve on the waste which I tinker with or tweek to get the r/o's sweet spot. 

Is there a way to boost pressure without an expensive noisey pump? 

No is the short answer. However, if you are sending 5 liters of waste to the drain to produce 1 liter of pure then restricting the waste more could help. (Old Merlins ran on a 5 to 1 ratio.)

Click to expand...

Spruce , you are the expert with this kind of thing , but can you explaine to me why you need a maximum of 50/50  waist/pure , I have a tds of around 90 and my production rate is around 75 pure to 25 waist , I have a booster pump and changed by first ro after 9 years , as I live in a soft water area I don’t dump much water , we produce around 6-8 thousand ltr of pure per week , I have a 25 ltr Di vessel and change the resin about every 15-18 months , so Ime not burning through that either , so oviously I don’t need to dump anything like 50% , my water is always 000 , as soon as I get a reading of 002 I change it , Ime intrested to know why my production rate is so good ??? 

Pjj said:

Spruce , you are the expert with this kind of thing , but can you explaine to me why you need a maximum of 50/50  waist/pure , I have a tds of around 90 and my production rate is around 75 pure to 25 waist , I have a booster pump and changed by first ro after 9 years , as I live in a soft water area I don’t dump much water , we produce around 6-8 thousand ltr of pure per week , I have a 25 ltr Di vessel and change the resin about every 15-18 months , so Ime not burning through that either , so oviously I don’t need to dump anything like 50% , my water is always 000 , as soon as I get a reading of 002 I change it , Ime intrested to know why my production rate is so good ??? 

Click to expand...

Im not 100% but id say maybe with tap water that outlandishly clean that its possible. very lucky. Id say for people in our game, if moving house, a main selling point or question for the estate agent would be ' Whats the Tds round there then?'  ?

ks789 said:

Im not 100% but id say maybe with tap water that outlandishly clean that its possible. very lucky. Id say for people in our game, if moving house, a main selling point or question for the estate agent would be ' Whats the Tds round there then?'  ?

Click to expand...

More importantly ''Does the house have a water meter?''

P4dstar said:

More importantly ''Does the house have a water meter?''

Click to expand...

yeh that too. 

Pjj said:

Spruce , you are the expert with this kind of thing , but can you explaine to me why you need a maximum of 50/50  waist/pure , I have a tds of around 90 and my production rate is around 75 pure to 25 waist , I have a booster pump and changed by first ro after 9 years , as I live in a soft water area I don’t dump much water , we produce around 6-8 thousand ltr of pure per week , I have a 25 ltr Di vessel and change the resin about every 15-18 months , so Ime not burning through that either , so oviously I don’t need to dump anything like 50% , my water is always 000 , as soon as I get a reading of 002 I change it , Ime intrested to know why my production rate is so good ??? 

Click to expand...

Hi @Pjj. When I said "You must always have at least a 50/50 pure to waste ratio whilst producing water", I meant that's the minimum that we need not maximum.  So 1/2 or more water used should be waste. Sorry if that came across uncleanly.

Our water isn't hard so it has given me a little leeway to play with ratios. For me I can get away with 50% waste to 50% pure, but sometimes the system works slightly better with a 55 to 45% ratio of waste to pure. My r/o will produce the same result if I up my waste to 60% and pure 40%. It starts to work slightly less efficient if I up my ratio to 70% waste and 30% pure. I put this down to the pressure on the membranes dropping off as my water pressure won't keep up with that ratio. (My w/p drops from 50psi to 40psi at 70/30.) If I go the other way to say 40 waste to 60 pure the tds of my pure increases by a couple of points - nothing much but percentage wise its a 50% increase. That's on the water pressure I have at home and its similar to what a couple of window cleaners in our area experience.

With these figures in mind and not being on a water meter, I aim for 50/50 but if I tweek it to 55/45 waste to pure, that's no big deal. If I up my ratio to 60/40 then my r/o is still performing at its most efficient, but I will be using more water. If I'm on a water meter then I don't want this. I will also use up the service life on my prefilters a little quicker.

But again, its all to do with 'economies of scale.'  If I'm on a water meter I might consider 40% waste to 60% pure. The longevity of my membrane will suffer and I will use more resin to polish my pure off, but it could be that the cost saving on my water bill more than compensates for the additional equipment costs.

Your water composition and quality could well allow you to squeeze that ratio higher as you experience with a booster pump. It could well be that if I had a booster pump I could get away with a similar waste to pure ratio as you. But as I haven't a booster pump I won't know this for sure.  I also have no plans to purchase one as I don't want to create any issues with the neighbours. (Our next door neighbour knows we use a lot of water as she see me filling my van everyday, but she doesn't know about the waste water that we send to the drain. I also clean her windows. Her back door is a couple of steps from my garage so I wouldn't like to disturb her peace with the noise of a booster pump running for 3 or 4 hours a day.)

One of the local lads has a booster pump on a small r/o. He produces water quicker, but he has never mentioned a change in rejection rates since adding the booster pump. But its a question I haven't asked him.

Alex Gardiner also mentioned ratios of pure to waste similar to what we experience. His normal water pressure at the shop is about 100psi. As has been said earlier, your are very fortunate to be able to successfully process water at those ratios.

Wow, thanks for all the detailed answers on here. My water is very high tds about 350 and seems low pressure ?. Takes around 5+ hours (can't remember exactly as still new) to fill almost 350l. There also doesn't seem to be a way to change the pure to waste ratio on the xline and I'm worrying I'm using a huge amount of water. When I next fill it I will check my water meter before and after. 

Also not too keen on using a booster pump for the noise reasons too. I'm sure I'll get my head round it all soon. 

spruce said:

Hi @Pjj. When I said "You must always have at least a 50/50 pure to waste ratio whilst producing water", I meant that's the minimum that we need not maximum.  So 1/2 or more water used should be waste. Sorry if that came across uncleanly.

Our water isn't hard so it has given me a little leeway to play with ratios. For me I can get away with 50% waste to 50% pure, but sometimes the system works slightly better with a 55 to 45% ratio of waste to pure. My r/o will produce the same result if I up my waste to 60% and pure 40%. It starts to work slightly less efficient if I up my ratio to 70% waste and 30% pure. I put this down to the pressure on the membranes dropping off as my water pressure won't keep up with that ratio. (My w/p drops from 50psi to 40psi at 70/30.) If I go the other way to say 40 waste to 60 pure the tds of my pure increases by a couple of points - nothing much but percentage wise its a 50% increase. That's on the water pressure I have at home and its similar to what a couple of window cleaners in our area experience.

With these figures in mind and not being on a water meter, I aim for 50/50 but if I tweek it to 55/45 waste to pure, that's no big deal. If I up my ratio to 60/40 then my r/o is still performing at its most efficient, but I will be using more water. If I'm on a water meter then I don't want this. I will also use up the service life on my prefilters a little quicker.

But again, its all to do with 'economies of scale.'  If I'm on a water meter I might consider 40% waste to 60% pure. The longevity of my membrane will suffer and I will use more resin to polish my pure off, but it could be that the cost saving on my water bill more than compensates for the additional equipment costs.

Your water composition and quality could well allow you to squeeze that ratio higher as you experience with a booster pump. It could well be that if I had a booster pump I could get away with a similar waste to pure ratio as you. But as I haven't a booster pump I won't know this for sure.  I also have no plans to purchase one as I don't want to create any issues with the neighbours. (Our next door neighbour knows we use a lot of water as she see me filling my van everyday, but she doesn't know about the waste water that we send to the drain. I also clean her windows. Her back door is a couple of steps from my garage so I wouldn't like to disturb her peace with the noise of a booster pump running for 3 or 4 hours a day.)

One of the local lads has a booster pump on a small r/o. He produces water quicker, but he has never mentioned a change in rejection rates since adding the booster pump. But its a question I haven't asked him.

Alex Gardiner also mentioned ratios of pure to waste similar to what we experience. His normal water pressure at the shop is about 100psi. As has been said earlier, your are very fortunate to be able to successfully process water at those ratios.

Click to expand...

Thanks spruce as always a thourough explanation , I am very happy with how my set up works but didn’t understand why it works the way it does , I can produce a 1000 ltr of pure in around two hours , Ime very impressed with the booster pump Oliver at Grippatank fitted , I can thoroughly recomend it ,it’s certainly not silent but with the van doors shut I would describe it as a light hum at 5 feet away and at 10 feet away you cannot hear it

Instead of using one of the booster pumps could I use a spare wfp I have? Would that work or would it be too slow and not habe enough flow? 

Paul Symonds said:

Instead of using one of the booster pumps could I use a spare wfp I have? Would that work or would it be too slow and not habe enough flow? 

Click to expand...

Off the top of my head, I can't remember why but no, a wfp pump isn't suitable 

It would be good if I could adjust my waste to pure ratio instead of 2/1 I don't need faster production as my auto shut off valve  aka the wife doesn't always check her phone so I would have a flood, but curious to know if adjusting the ratio would make any difference on the life span of pre-filters and membranes

You can't use a WFP pump. Someone will pop up and say they do i'm sure but in the past @spruce has asked someone to show us the set up as we would all love to be able to do that and never got a response.

As regards setup, could you not fill some type of reservoir from the garden hose and also in that reservoir is the suction hose from the wfp pump with the pump end going into the prefilters? As long as you matched the flow you wouldn't overfill the reservoir or run out of water. The wfp pump also has a pressure shut off for when the tank is full and shuts the fill valve. Then maybe have some shutoff valve on the small reservoir to the shut off garden hose. Or you could even use a wfp trolley system to do it? 

Only thoughts, not tried it. Just can't think why it wouldn't work but as I said I am an ro newbie so probably some reason why it wouldn't. 

Iron Giant said:

It would be good if I could adjust my waste to pure ratio instead of 2/1 I don't need faster production as my auto shut off valve  aka the wife doesn't always check her phone so I would have a flood, but curious to know if adjusting the ratio would make any difference on the life span of pre-filters and membranes

Click to expand...

Your prefilters should last longer between changes as they aren't processing as much water. If your current ratio is 2 waste to 1 pure and you restrict the waste to 1 waste to 1 pure then then prefilters will have to process 1 litre of water less for each litre of pure you make.

I personally think that @Pjj is extremely fortunate as his supply water is soft and is probably very low in the dissolved solids that block up membrane pores, such as calcium. The very fact that his membrane has lasted as long as it has is testimony to his situation being one of uniqueness.

This subject was discussed in great detail on CIU quite a number of years ago. The general concensious back then was restricting the waste saved water costs, increased resin costs and reduced the membrane's longevity. Of course there was no scientific conclusions as it was each users opinion based on his 'experience'. Users reporting their findings were from all over the country with different compositions of water. 

The discussion also brought up the hot topic of replacing the carbon block filter to its manufacturers declared service life. Some were adamant that replacing the prefilters less often and ignoring service life figures saved money overall even if it meant replacing membranes prematurely.

@spruce thank you ? I think you have worked hard under your new honorary title ?, I may well try a different tap on my R/O recommended by you last year or maybe have a go with the one I have and do a small trial. 

Paul Symonds said:

Instead of using one of the booster pumps could I use a spare wfp I have? Would that work or would it be too slow and not habe enough flow? 

Click to expand...

At 50 psi my 4040 uses 4lpm of water with a 50/50 pure to waste ratio. With your water tds your will probably need a 2 to 1 ratio. At this rate your wfp pump wouldn't be able to deliver the flow rate at the pressure you need.

I have an old friend whose son is a window cleaner. This old friend process water at his home for his son into a 1000 liter IBC tank. He has a small 450gpd r/o and uses a Vyair Chen pump as a booster pump. But he has the pump rigged up to a mechanical timer. The pump works for 15 minutes and switches off for 15 minutes in a cycle until the IBC is full. This timer is to allow the pump to cool down as it gets warm.