craigw

  • Posts: 28
not happy with merlin RO
« on: June 24, 2005, 08:48:12 pm »
I got a new merlin RO 2 weeks ago for my static system, tested it out, TDS coming in read 450, after the merlin read 40, contacted supplier and sent it back cause it may have been faulty and they sent me back a brand new one and said that they could not find anything wrong with the old one. The new one reads 244 in and  out 19, so i took my built in tds meter out of the van to double check the one on the RO, the van one said 486 in and 32 out, so one of them must be faulty.
I also borrowed a hand held tds meter off of a friend it read 286in and 25 out. Why do i get three different readings off of three different meters when i tested them one after the other?
 If it is a true reading of 19 is this exceptable or should i send it back and pay more money and get a different RO, if so can u recommend any the will get the reading down further what is the best reading that i can expect from a more expensive RO?
I need to buy a booster pump too because the merlin will only do 25 litres in 40 mins, also been told if i increase the pressure the TDS reading should come down even more.
Please help doing my head in, should i send it back or not? Can u recommend any better ones i have seen some 40inch ones what are these like? What TDS readings could this take the water down too?
THANKS

ian wigglesworth

  • Posts: 11
Re: not happy with merlin RO
« Reply #1 on: June 24, 2005, 09:16:21 pm »
Craigw,

That sounds interesting, looking at buying one of these myself!
I have read that most of the RO units just trickle the pure water out, unless you get a very big one.

I think the increase in pressure just means that there is less waste, eg at low pressure you may get a 1:3 ratio (1 pure water to 3 parts waste)
by increasing the pressure this just brings the ratio to 1:1.
I dont know if it fills any quicker though.

I have also read that you still need a DI resin tank after the Merlin RO unit to bring the reading down to 000

Hopefully somebody with loads more experience will be able to put us both right!

Cheers Ian

matt

Re: not happy with merlin RO
« Reply #2 on: June 24, 2005, 09:17:06 pm »
the Merlin does have higher TDS output than a normal RO

well thats what i have been led to belive

s.hughes

Re: not happy with merlin RO
« Reply #3 on: June 24, 2005, 10:24:41 pm »
I've only just set my ro system up and I find that the ratio is 1 pure to 3 waste and it just trickles out. This is something I'm not happy with and will find a way round it as I cant really leave the system on 24 hours at the moment.
My system has a di unit attached and this brings the tds down to 000. Without the di the tds is around 45 and 270 from normal tap.
I have tried just using the di and not the ro but the tds is still to high to use. It may be that the di tank is really small and I have been told that you go through lots of resin doing it this way. I may have to go down that road until I set up a proper system.

I hope you get it sorted out. I think that in a few years time we will all look back and wonder what the problem was.

Steveyboy

Mike_Boxall

  • Posts: 1394
Re: not happy with merlin RO
« Reply #4 on: June 24, 2005, 10:43:38 pm »
I have also read that you still need a DI resin tank after the Merlin RO unit to bring the reading down to 000

Hi

Yes, the figures you gave seem about right - you do need a DI filter after the Merlin to bring it down to 0 TDS. We will be stocking the Merlin RO units shortly and we hope to produce a simple user guide for it. They can be a bit confusing to set up and there seems to be conflicting advice about what you can and can't expect to get from it.

I'd be interested to know what output you eventually get from it.

Regards

Mike

Will let you know ehen we have more info.

craigw

  • Posts: 28
Re: not happy with merlin RO
« Reply #5 on: June 25, 2005, 04:02:07 pm »
is 40tds good from a ro???

Re: not happy with merlin RO
« Reply #6 on: June 25, 2005, 04:10:16 pm »
i have three 25ltr di chambers with no ro unit my reading going in is 380 thru the filler chamber and 000 out of the reel di chamber my resin lasts 4 weeks but i use 700ltr 6 days a week.I also was looking into a merlin not sure now?

H h20

Re: not happy with merlin RO
« Reply #7 on: June 25, 2005, 04:23:03 pm »
my merlin is producing 25ltrs in 12 minutes :),iv`e not yet started using the water yet just storing it until i get my di resin soon. :-\

H h20

Re: not happy with merlin RO
« Reply #8 on: June 25, 2005, 04:39:22 pm »
my merlin is producing 25ltrs in 12 minutes :),iv`e not yet started using the water yet just storing it until i get my di resin soon. :-\
Forget my last post,im drinkin cold carlsberg export ;D ;),it`s doing 20 ltrs in 11 mins and thats official!

UBA1

Re: not happy with merlin RO
« Reply #9 on: June 25, 2005, 05:18:04 pm »
I`ve a Titan RO, my TDS reads 380, after the RO it reads between 15-20, then goes thru` DI bringing it down to 000. After approx a week it reads 006, week 2 010, week 3, about 015.

I normally change resin at about 2.5/3 weeks, as it reaches about 015.

I`m fairly happy with the above.

Steve

H h20

Re: not happy with merlin RO
« Reply #10 on: June 25, 2005, 05:22:18 pm »
I`ve a Titan RO, my TDS reads 380, after the RO it reads between 15-20, then goes thru` DI bringing it down to 000. After approx a week it reads 006, week 2 010, week 3, about 015.

I normally change resin at about 2.5/3 weeks, as it reaches about 015.

I`m fairly happy with the above.

Steve
How much resin are you using ie what size is your resin vessel for you to need to change every 2-3 weeks and how much water are you producing ?

UBA1

Re: not happy with merlin RO
« Reply #11 on: June 25, 2005, 05:53:14 pm »
It`s only a 10" (my vessel, that is  ;D )

I produce approx 400 litres in 6 hrs. Saying that, my mains pressure is very good. The psi is 80 from mains, and that`s without a booster pump. So i`m very happy with that.

Steve

williamx

Re: not happy with merlin RO
« Reply #12 on: June 25, 2005, 06:57:00 pm »
Easycleanwindows

i have three 25ltr di chambers with no ro unit my reading going in is 380 thru the filler chamber and 000 out of the reel di chamber my resin lasts 4 weeks but i use 700ltr 6 days a week.I also was looking into a merlin not sure now?

Am I right you produce 16800 litres of water before you change you di resin? when the water reading going in is 380.

The reason I ask is I'm in a softwater area and don't need a ro unit just a di tank, my water readings are 70 going in and 000 coming out, but I have to change my 25 litres of resin every 4500 or 5000 litres which means I am using more resin than you?

From what I can gather you have 3 di units with the water going from one to the next and then the next one? if so would you expect me to be able to purify more water because my tds reading are much lower at the start of the process?

sair

  • Posts: 682
Re: not happy with merlin RO
« Reply #13 on: June 25, 2005, 08:21:56 pm »
thats because you only use 20% percent of your resin before change , if you use two cylinders you will get at 50 - 75 % better life from your resin , due to the fact that resin can still bring down tds of water which will mean that second cylinder wont have too work so hard.  thats easiest way to explain .07944 227635.. if dont understand or want to know more can call me
Essentially Pure Ltd

jsm

  • Posts: 558
Re: not happy with merlin RO
« Reply #14 on: June 25, 2005, 08:54:31 pm »
I've only just set my ro system up and I find that the ratio is 1 pure to 3 waste and it just trickles out. This is something I'm not happy with and will find a way round it as I cant really leave the system on 24 hours at the moment.
My system has a di unit attached and this brings the tds down to 000. Without the di the tds is around 45 and 270 from normal tap.
I have tried just using the di and not the ro but the tds is still to high to use. It may be that the di tank is really small and I have been told that you go through lots of resin doing it this way. I may have to go down that road until I set up a proper system.

I hope you get it sorted out. I think that in a few years time we will all look back and wonder what the problem was.

Steveyboy

steve if you using the 10inch Di from RO-man make sure the resin cartridge  inside the Di is the right way round , as mine was put in upside down - It took me a week of high readings before I took it apart and found it upside down  >:( turned it round - bang 000
John Malone
JSM. Window & General Cleaning
(  North Wales  )
Giving homes a shine sicne 1989

one of the early gang of wfp er's ---- remember , when you cant see out - give JSM a shout

craigw

  • Posts: 28
Re: not happy with merlin RO
« Reply #15 on: June 28, 2005, 10:04:56 pm »
 can some plz help me plz

williamx

Re: not happy with merlin RO
« Reply #16 on: June 28, 2005, 10:23:25 pm »
Sair

What would happen if I used 3 - 4 or more di units

cedric

  • Posts: 36
Re: not happy with merlin RO
« Reply #17 on: July 19, 2005, 10:20:10 am »
It's true that the Merlin doesn't purify as much as a 40 inch RO.
In London we have a tds reading of about 500ppm

after a 40 inch RO, with a ratio of 1:3 and no booster pump, we have 10ppm or below (4 ppm in summer time). One of our customer in Ireland has 1ppm because ts tap water is 120ppm.

after a Merlin system we have 40ppm.

it means that with a 40" RO with 10ppm you will make 50 000L of pure water with a 25L bag of resin

with a Merlin RO with 40 ppm you will make 12500L of pure water with a 25L bag of resin.

The Merlin purification is acceptable for the price you pay for it.
If you want a booster pump for the Merlin we have one specially made for it for those who have a pressure of less than 30 psi.



sair

  • Posts: 682
Re: not happy with merlin RO
« Reply #18 on: July 19, 2005, 04:37:07 pm »
hi could some one please change my name from SAIR
 to TONY  thank you
have tryed but cant do it
william we only use two vessels 6x 35 takes half sack resin each find it just as efficent as two larger vessels .have in past used four 6x18 changing two at a time worked quite well

on subject R/O we use 40x40 all makes find them to be robust hard wearing and if looked after last years . our tds is 325 and we take it down  to 002     003  it makes about 250 liters a hour qiute happily we have to restrict water as our presure is 125plus on our van mounts we do boost all 40x40 single or twinR/O  trying to get them to run at 85-90 psi with a good flow rate as well find this works well ...

 cost to cost each time i would buy a 40x40 cheaper to run less resin used at end result to 000 the water
Essentially Pure Ltd