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How to get best results filling tank from DI Vessel?

WCF

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So if im understanding this correctly, I can keep my setup the way it is apart from one new hole I would need in the top of my tank. RO connects to my 11Ltr DI then connects to the new hole which I'm assuming I'll have to fit some kind of connection to?
Yes. The kit I linked to has a float valve which needs to go through the side of the tank (not sure but there will be ones that mount in top) and that has 1/4" push fit john guest pipe connection on which is same as the RO unit I linked to. 

To be honest Doug is much better placed than me to explain RO system. He sells small 450gpd systems and I am sure he can help with an auto shut off system that would suit. 

 
Hey guys, I'm just wondering what the best method would be for filling my tank using a DI vessel.

I currently have 3 DI's 2 in the van and one for the tap that I just bought from Daqua, however when I fill from my tap through the DI the water is coming out at around 50-60 ppm. My tap water is 142 ppm are these normal numbers or should I be doing something else to bring the ppm down more then that? 

I guess it has a lot to do with the pressure from the tap being much higher then a pump can provide but maybe you guys have some tips out there.

Thanks.
If you are just using DI vessels then pressure is not an issue. DI vessel’s don’t perform better with pressure. Pressure is important for RO use. 

 
If you are just using DI vessels then pressure is not an issue. DI vessel’s don’t perform better with pressure. Pressure is important for RO use. 
Wait so are you saying that a DI connected directly to my tap should give the same output TDS then what a 100 psi pump would? That doesn't sound right to me. Perhaps pressure isnt the issue here and more a case of volume of water passing through the vessel?

I can achive 000 easily using the pump in the van, but from the tap is a different story.

 
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Wait so are you saying that a DI connected directly to my tap should give the same output TDS then what a 100 psi pump would? That doesn't sound right to me. Perhaps pressure isnt the issue here and more a case of volume of water passing through the vessel?

I can achive 000 easily using the pump in the van, but from the tap is a different story.
I think what he meant was that increasing the pressure doesn't help a DI vessel but increasing the pressure on a RO can help if it's too low.

I believe DI is a chemical reaction that lowers the TDS. If your van pump was flat out at 5.2l/min on an 11 lts DI unit the water would be in the resin for 2 minutes. Where as a tap can in theory flow up to 12 lts per min (not many go that high). 

Is it difficult to swap the double DI and temp fit it to the tap as that would prove there is something wrong with the new DI setup? My guess is that the double DI is only seeing a max of 5lts/min where tap could be higher. It might be worth half closing the tap on the new DI to reduce the flow and see if the tds drops? I believe that if you push water through a DI too fast it might not reduce tds as much as it could.

 
I get where you are coming from. Just for future ref you would use a little over double water that you currently use now if you RO. 

Just to give you an idea 350 lts  x 2 = 750 lts per week x 4 = 3000 lts per month.  

Water cost= £1.922 / m3 (!000 liters) 

Waste = £1.269 / m3 (!000 liters) 

Using DI

water = £1.9922 x 3  = £5.77

waste = £1.269 x 3  = £3.81 (waste is charged same as meter reading)

Total water cost using DI = £9.57

Using RO

 £1.9922 x 6 (3000 liters pure 3000 liters waste) = £11.53

£1.269 x 6 ( unless you fit meter and contact your water board) = £7.61

Total water cost if using RO = £19.14. 

So you will spend £10 a month on extra water using RO than DI!!!

Using the Grippa tank resin calculator 3000lts per month at 142ppm will cost £77 per month based on a 25 lts bag of resin costing £100.

If an RO is only 90% efficient your resin costs would be more like £7 a month!!!!

Looking at the numbers using RO & DI would cost you less than £30 a month. Where as just using DI will cost you close to £90 a month!!!! 

So if you bought a 450 gpd RO system from ebay at £195 it would pay for itself in about 3.5 months!!!

The above is simplifying things but it does give you an idea of the differing costs of DI vs RO. 

I haven't taken into consideration changing filters but thats not much on the volume of water you are using and if/when your business grows the savings will be significantly higher as a 450gpd RO system should easily fill your tank overnight as long as you have reasonable tap pressure. 

Anyway it gives you something to think about.

As for getting your tds down on your DI it might be worth lowering your pressure going into the DI and give the DI a shake.
Interesting, That's the trouble with having a water meter though it can bump up costs, pretty sure and someone correct me if I am wrong like @spruce a standard R/O produces 2ltrs of waste to 1ltr of pure unlike a 40/40 or 40/21 which produces 50-50 pure and waste the waterboard will have to be contacted to see if they will waive the extra cost for the waste water going down the drain,

 This would work out cheaper as when you consider that @Gary090118 has already gone too the expense of buying 3 di vessels and bags of resin which if the di vessels were brand new from a supplier a 7ltr vessel is around £80 x 3 that's £240 then 2 bags of resin lets say £90x 2 that's £180 so straight out the blocks he has spent £420 upwards and looking to spend more. 

 
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Interesting, That's the trouble with having a water meter though it can bump up costs, pretty sure and someone correct me if I am wrong like @spruce a standard R/O produces 2ltrs of waste to 1ltr of pure unlike a 40/40 or 40/21 which produces 50-50 pure and waste the waterboard will have to be contacted to see if they will waive the extra cost for the waste water going down the drain,

 This would work out cheaper as when you consider that @Gary090118 has already gone too the expense of buying 3 di vessels and bags of resin which if the di vessels were brand new from a supplier a 7ltr vessel is around £80 x 3 that's £240 then 2 bags of resin lets say £90x 2 that's £180 so straight out the blocks he has spent £420 upwards and looking to spend more. 
@Gary090118has a similar water quality to ours. It ranges from 120 to 150ppm.

We have a 4040 with an HF5 membrane. Our best waste to pure ratio is 55% waste to 45% pure. Our tap water consumption is 77,000 liters every 4 months on average. So we use approx 12,000 liters of pure water a month. Waste is slightly higher than 2 liters per minute and pure is just slightly less than 2 lpm.

My membrane reduces the tap water tds to 3ppm. My 7 liter di vessel has the resin replaced once a year. So a 25liter bag lasts me 4 years.

We aren't on a water meter so I haven't bothered about water costs per cubic meter, but these are available on @Gary090118's water bill.

I believe that @Gary090118is getting too hung up about waste water. Yes the initial costs to set up a good quality r/o are expensive but with good quality resin in short supply (and has been for quite a while now) getting an r/o is future proofing your business. You can't clean windows with water of 150ppm but you can just get away with cleaning windows at 3ppm.

Water is the essence of wfp window cleaning. If you haven't got enough water you can't grow your business. If your water quality is iffy then you could very quickly ruin your reputation with one bad clean.

As has been previously mentioned, having an r/o will quickly reduce your resin costs. I believe those cost saving will very quickly cover the r/o investment. Saying this we also realise that new starters don't always have the finance available to invest these amounts. Try to add a £1 to every quote to cover your water bill.

We managed with a 450gpd for 6 years before going to a 4040. The second hand 1000 liter IBC tank I have in my garage is now 14 years old. A 450gpd r/o isn't that expensive but you also need to buy one from a supplier such as @doug atkinson. The stuff he sells will have quality membranes fitted; not cheap Chinese copies that's efficiency and longevity are never on a par with USA manufactured membranes. This is why he's prices are a little more than some r/o purchased from Ebay.

 
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I believe that @Gary090118is getting too hung up about waste water. Yes the initial costs to set up a good quality r/o are expensive but with good quality resin in short supply (and has been for quite a while now) getting an r/o is future proofing your business. You can't clean windows with water of 150ppm but you can just get away with cleaning windows at 3ppm.
I think they all do but by comparison just to buy a standard R/O from a reputable supplier the costs can be almost the same to buy an R/O over buying a di vessel and and bag of resin that will last a few weeks if they are busy enough, 

I know in the past you have mentioned another cleaner you know in your area who just has a standard R/O with a booster pump and manages just fine, I started off with a R/O then tried just di only the increase in costs was almost immediately noticeable and I could foresee my costs were going to go from £10's per annum to £100's 

 
@Gary090118has a similar water quality to ours. It ranges from 120 to 150ppm.

We have a 4040 with an HF5 membrane. Our best waste to pure ratio is 55% waste to 45% pure. Our tap water consumption is 77,000 liters every 4 months on average. So we use approx 12,000 liters of pure water a month. Waste is slightly higher than 2 liters per minute and pure is just slightly less than 2 lpm.

My membrane reduces the tap water tds to 3ppm. My 7 liter di vessel has the resin replaced once a year. So a 25liter bag lasts me 4 years.

We aren't on a water meter so I haven't bothered about water costs per cubic meter, but these are available on @Gary090118's water bill.

I believe that @Gary090118is getting too hung up about waste water. Yes the initial costs to set up a good quality r/o are expensive but with good quality resin in short supply (and has been for quite a while now) getting an r/o is future proofing your business. You can't clean windows with water of 150ppm but you can just get away with cleaning windows at 3ppm.

Water is the essence of wfp window cleaning. If you haven't got enough water you can't grow your business. If your water quality is iffy then you could very quickly ruin your reputation with one bad clean.

As has been previously mentioned, having an r/o will quickly reduce your resin costs. I believe those cost saving will very quickly cover the r/o investment. Saying this we also realise that new starters don't always have the finance available to invest these amounts.

We managed with a 450gpd for 6 years before going to a 4040. The second hand 1000 liter IBC tank I have in my garage is now 14 years old. A 450gpd r/o isn't that expensive but you also need to buy one from a supplier such as @doug atkinson. The stuff he sells will have quality membranes fitted; not cheap Chinese copies that's efficiency and longevity are never on a par with USA manufactured membranes. This is why he's prices are a little more than some r/o purchased from Ebay.
I'm definitely looking into it but you're right I don't exactly have stacks of cash to invest in the business right now. I can probably drop 300 on a cheaper RO for now it's just the issue of setting it up in the van.

I check my water quality before every round, it's at 000 now and has been for a few weeks the resin does work for me at this stage because I'm only working 2 days a week. The buisness grows every week though (I do a lot of canvassing) by the end of this year or early next year I will probably be in a position to upgrade my van and my system.

We are talking about moving house as well soon and I'm going to look for a place without a water meter and preferably a garage to setup an RO unit

 
@Gary090118has a similar water quality to ours. It ranges from 120 to 150ppm.

We have a 4040 with an HF5 membrane. Our best waste to pure ratio is 55% waste to 45% pure. Our tap water consumption is 77,000 liters every 4 months on average. So we use approx 12,000 liters of pure water a month. Waste is slightly higher than 2 liters per minute and pure is just slightly less than 2 lpm.

My membrane reduces the tap water tds to 3ppm. My 7 liter di vessel has the resin replaced once a year. So a 25liter bag lasts me 4 years.

We aren't on a water meter so I haven't bothered about water costs per cubic meter, but these are available on @Gary090118's water bill.

I believe that @Gary090118is getting too hung up about waste water. Yes the initial costs to set up a good quality r/o are expensive but with good quality resin in short supply (and has been for quite a while now) getting an r/o is future proofing your business. You can't clean windows with water of 150ppm but you can just get away with cleaning windows at 3ppm.

Water is the essence of wfp window cleaning. If you haven't got enough water you can't grow your business. If your water quality is iffy then you could very quickly ruin your reputation with one bad clean.

As has been previously mentioned, having an r/o will quickly reduce your resin costs. I believe those cost saving will very quickly cover the r/o investment. Saying this we also realise that new starters don't always have the finance available to invest these amounts.

We managed with a 450gpd for 6 years before going to a 4040. The second hand 1000 liter IBC tank I have in my garage is now 14 years old. A 450gpd r/o isn't that expensive but you also need to buy one from a supplier such as @doug atkinson. The stuff he sells will have quality membranes fitted; not cheap Chinese copies that's efficiency and longevity are never on a par with USA manufactured membranes. This is why he's prices are a little more than some r/o purchased from Ebay.
Just thinking about the decent usa membranes we use. Hopefully it doesn't all go totally  tits up over there and the supply of membranes stops. I may get one in advance. Ive got a sister and nieces in the states, she works for the american embassy and has been in afghanistan, pakistan, trained to use glock etc, yet she is nervous and stays in a cabin with a niece in the woods away from the city sometimes. Im sure america is on a precipice.

 
I'm definitely looking into it but you're right I don't exactly have stacks of cash to invest in the business right now. I can probably drop 300 on a cheaper RO for now it's just the issue of setting it up in the van.

I check my water quality before every round, it's at 000 now and has been for a few weeks the resin does work for me at this stage because I'm only working 2 days a week. The buisness grows every week though (I do a lot of canvassing) by the end of this year or early next year I will probably be in a position to upgrade my van and my system.

We are talking about moving house as well soon and I'm going to look for a place without a water meter and preferably a garage to setup an RO unit
Far better to have a static set up at home, R/O in a shed or even one of those cheap plastic chests and insulate it and a water butt or two can be bought cheaply enough and don't look so bad in any garden, I have been wfp over 12 years and mine is in a shed and pure goes into a 350ltr water butt all housed in a shed.

As for upgrading your system there isn't a need to spend on a newer bigger system either, I have a 350ltr upright tank and as and when needed I fill one or two 25ltr containers in the van giving me up to 400ltrs the containers can be bought pre-used of Ebay for cheap enough. 

 
The first clean is the one that takes the most water if done properly first time. Then on, water consumption will be lower. At one time I would never have considered a tank smaller 500 liters in a van for a single cleaner working full time. But experience has taught me that we can reduce that and carry less. I wouldn't go below 350liters though.

 
The first clean is the one that takes the most water if done properly first time. Then on, water consumption will be lower. At one time I would never have considered a tank smaller 500 liters in a van for a single cleaner working full time. But experience has taught me that we can reduce that and carry less. I wouldn't go below 350liters though.
Yeah I did 10 first cleans last week and used my full tank on them they hadn't been cleaned in years. 

I do like the idea of simply filling more barrels to top my water up although I still need to upgrade my van I don't have the space I need for everything.

 
Yeah I did 10 first cleans last week and used my full tank on them they hadn't been cleaned in years. 

I do like the idea of simply filling more barrels to top my water up although I still need to upgrade my van I don't have the space I need for everything.
? Not many of us do.

 
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