[a900]

Hi guys

I recently bit the bullet and upgraded my 450gpd to a 4040. Starting to wonder if I was better off with what I had. This is getting expensive inc time and still not happy with output tds.

Im getting a TDS of 34 off my tap pressure (45PSI) and cant get much better than 29 with the pump on 80 - 100psi depending on waste ratio. My input is 320.

Weird thing is the membrane has been back in the housing to the supplier for testing and they got down to 13 with tap pressure of 55psi and similar input tds.

SO what am I doing wrong? I have noticed that the prefilters were bubbling air out the outlet but no leaks and they were when they were bubbling flowing a lot slower than the tap??? they don't seem to be bubbling now.

[Frankybadboy]

when you play with the waste pipe,are you letting it run for a time before you do a new tds reading ?

[Steve foster]

I get Zero TDS from 130 tap and 75 psi mains. The prefilters do not make much if any difference to the TDS. If you read the info on the Gaps website it gives you an idea on how to set your RO's sweetspot.

[jk999]

I set all my 4040ro up three weeks ago it's coming from membrane at 008tds it's already coming out of resin at 003 is this normal after three weeks it's only running for around seven hours in total a day

[Don Kee]

I set all my 4040ro up three weeks ago it's coming from membrane at 008tds it's already coming out of resin at 003 is this normal after three weeks it's only running for around seven hours in total a day

How big is your D.I?if your R.O product is 8ppm, your post resin tds should stay at 0 for a while with a decent sizes D.I

[jk999]

11ltrs

[Don Kee]

11ltrs

Should last longer than 3weeks, how much water do you produce a week?

[jk999]

About 1500 a day five days a week

[Clever Forum Name]

About 1500 a day five days a week

Your resin would last 4 weeks or less.

Double DI will help

[jk999]

Thinking off changing vessel for two twenty inch ones I think they will last twice as long as one 11 ltr one

[Clever Forum Name]

Double di will more cost effective.

we use a 100L DI's and change the resin every 2 years or so 

[a900]

I've been toying with different waste ratios And leaving time between testing the tds. No luck still around 30.

Odd that it went back to supplier and they got better tds from this membrane.

[Avo]

Yes it should be run for 10 to 20 mins before taking this reading and it will settle but having said that I've been getting 30 Tds from 350 as well, love to no how people get 10 and below. 
What system is it?

[Avo]

I set all my 4040ro up three weeks ago it's coming from membrane at 008tds it's already coming out of resin at 003 is this normal after three weeks it's only running for around seven hours in total a day

god that's impossible ain't it lol
U may find its 3 after you just done a tap reading throw that away and do it again and it will be zero guaranteed.

[jk999]

Will try that avo cheers bud

[PoleKing]

About 1500 a day five days a week

7,500 litres of pure a week? For one van?

[jk999]

Who mentioned one van ?

[PoleKing]

Who mentioned one van ?

Perhaps my mistake.
I assumed one van as it seemed like a newb question.

[jk999]

Been using pole system 14 years now

[Dave Mills]

Hi guys

I recently bit the bullet and upgraded my 450gpd to a 4040. Starting to wonder if I was better off with what I had. This is getting expensive inc time and still not happy with output tds.

Im getting a TDS of 34 off my tap pressure (45PSI) and cant get much better than 29 with the pump on 80 - 100psi depending on waste ratio. My input is 320.

Weird thing is the membrane has been back in the housing to the supplier for testing and they got down to 13 with tap pressure of 55psi and similar input tds.

SO what am I doing wrong? I have noticed that the prefilters were bubbling air out the outlet but no leaks and they were when they were bubbling flowing a lot slower than the tap??? they don't seem to be bubbling now.

Mine at 70psi gives 6 from 330 with an HF4 membrane (better than HF5 at higher pressures).  When I didnt have a booster pump mine was outputting in the mid 20s like yours.

I think its the pressure.   If youre measuring it before bubbling prefilters youre probably getting a false reading.  If after then I dont know.