[rajivanoj]

I bought an assembled RO, but membrane was Vontron, which i had fixed from A to z , plumbing, fixing the wall mounting etc. had some leaks and i had fixed it. But the problem is, i get very good water, mostly get rejected. almost 90-95% wasted, only less water gets into tank. What is problem?

I thought RO would waste maximum 40-45%. But in my case i get only 5% good water. What should i do?

[RajaTaurus]

^^It could be that your main pump pressure is not sufficient and not regulated. Recovery is directly related to TDS and pumping pressure needed is proportional to TDS. Higher the pressure more the recovery and vice versa. Please check the required pressure for the inlet TDS and adjust pump pressure.

[Mortis]

If there is a TDS control valve, which just looks like a screw, it might be fully tight and hence more water is being rejected. You can locate and loosen this by a turn or two and check again

[RajaTaurus]

^^TDS controller only bypasses RO membrane to mix some inlet water with output water. Opening it up will not solve the problem and you will only get un permeated water.

[rajivanoj]

Originally Posted by Mortis

If there is a TDS control valve, which just looks like a screw, it might be fully tight and hence more water is being rejected. You can locate and loosen this by a turn or two and check again

yes, i had tried, but it solve the problem but as RajaTaurus said, if we get more water then its bit salty. So For good sweet water, i had adjusted TDS controller. Though i get desired result. but the quantity is too low. which has more than 90% waste water.

Originally Posted by RajaTaurus

^^It could be that your main pump pressure is not sufficient and not regulated. Recovery is directly related to TDS and pumping pressure needed is proportional to TDS. Higher the pressure more the recovery and vice versa. Please check the required pressure for the inlet TDS and adjust pump pressure.

I think TDS is not much problem, but as you said the pressure of booster pump may be problem. how should i adjust the pressure of the pump? i had not seen any adjustment in booster pump. please clarify.

[RajaTaurus]

^^Different makers have different mechanism to set/adjust main pump pressure. My suggestion would be to check with the manufacturer. May be there are no adjustments and you might have to change the pump itself.

[Mortis]

If your TDS is high at say 1000 ppm and you are trying to get it below 50, it is expected that the amount of waste water rejected will be more and output will be slower, no two ways about it. Increasing the pump pressure or adding a second membrane can help to some extent

[RajaTaurus]

- To bring TDS from 1000 to 50 is called Salt rejection %.
- To get enough quantity of Permeate is called Recovery %.
With right design, we can get as much as 50% recovery (meaning 50% wastage) and also bring TDS from 1000 to 50.

[revtech]

any one used ALFA water purifiers ? any reviews in comparison to Eureka forbes ?


rev

[mxx]

Between Kent and HUL pureit (RO+UV models), generally which one has lower maintenance cost?

[sgiitk]

@mmx; According to my son's experience, the Kent units start having frequent issues about two to three years down to line. In other words they are not 'built to last'. HUL may be better in this regard. However, availability on maintenance in terms of both ease and cost may be another issue. So I suggest check with an independent maintenance chap before putting down your money.

[Mortis]

My Kent Grand Plus is running flawlessly after 4 years only needed to replace the cartridges which are easy to do yourself also if necessary

[redbaron91]

I bought ZeroB Emerald (from Ion Exchange India) model yesterday.
Cost - 16000/-

Tap water is sourced from apartment's Borewell, TDS was 1060.

Output TDS observed - 80

[rohan_iitr]

Originally Posted by sgiitk

the Kent units start having frequent issues about two to three years down to line. In other words they are not 'built to last'.

+1
I will have to agree with this. My Kent Pearl unit worked properly for the initial 3 years, with just the annual replacement of filters. After that, the motor, RO membrane and control unit needed replacement.

The RO membrane again needed replacement after exactly 1 year (the plastic got cracked and water was leaking).

Now, after 4-5 years, only the plastic body is same as what came from the factory. Rest everything has been replaced.

A close friend also had a similar experience with his Kent Grand Plus. So many parts required replacement after 5 years that he decided to buy a new one instead.

Rohan

[mxx]

Originally Posted by sgiitk

@mmx; According to my son's experience, the Kent units start having frequent issues about two to three years down to line. In other words they are not 'built to last'. HUL may be better in this regard. However, availability on maintenance in terms of both ease and cost may be another issue. So I suggest check with an independent maintenance chap before putting down your money.

thanks. this has been the general feedback I got from others too.
Finally purchased HUL pureit RO+UV mineral classic.