[chinkara]

Originally Posted by Iyencar

Regardless of the brand, choose a simple UV purifier and not an RO. The RO filters end up wasting a lot of water due to the way they work. They are also overkill in most cases and can be crazy expensive to repair. Lastly, there are some US EPA studies showing the chemicals used in the filters may be toxic.

Actually we need an RO. Our earlier version of aquaguard (UV only) developed moss in its pipelines etc. which we understood that was due to organic matter and filters were getting choked every 2 months due to TDS levels in our input water. We switched to RO+UV and had no issues for 5 years (apart from the ever increasing maintenance costs).

The same aquaguard is working at my in-laws'place in Kolkata for the past 5 years without trouble. So clearly, the issue was input water in Gurugram.

[sgiitk]

Originally Posted by Miyata

Yes Sir. I think the measurement displayed could be inaccurate.

My rationale - pH meters are very sensitive precision instruments. From the memory of my using them, they need to calibrated on a three point scale (cubic) every few days for accurate measurements. Some do it on a two point scale too (linear), which will work fine depending on the range being measured and how closee the they are to the calibration points.

More than anything the vessel you take out the water in can be the real culprit. Remember pH is a log scale and any variation from the nominal 7.0 will send the figures into outer space. It can be a case of Garbage in, garbage out.

[diyguy]

I have a US purchased RO and just installed it after installing a pressure pump at home. I am seeing TDS of 300ppm post purification. Pre-purification is 2000ppm. My RO has a re-mineral attachment so unsure if the TDS is intentional or if the US membrane cannot handle the 2000 TDS. I plan to purchase a India product membrane if this is a membrane issue.

[Miyata]

Originally Posted by diyguy

RO has a re-mineral attachment so unsure if the TDS is intentional or if the US membrane cannot handle the 2000 TDS.

I wouldn't trust a remineralization in the filter process. You could just bypass this stage and check again for the TDS reading?

My guess is that the RO membrane itself should be alright and perfectly capable of handling the 2000 water.

Also, there is no right answer to what a "good TDS value" is. These are rather imprecise in their description and generally, as you'd already be well aware, lower the TDS value, lower are the dissolved minerals etc (both good and harmful ones). Under a threshold, it's an important number but by no means a critical one. If the remineralization step isn't some strange black magic, you might be consuming healthier water than many of us that are taking in at lower TDS.

[diyguy]

Originally Posted by Miyata

You could just bypass this stage and check again for the TDS reading?
My guess is that the RO membrane itself should be alright and perfectly capable of handling the 2000 water.

Thanks for the reply, I will divert the water prior to the remineralizarion phase to check the TDS at that point. I will drop a note to customer support as well to check on this. Earlier when I had told them I have 2000 TDS, they replied that they do not recommend their system in such a scenario. However their site lists the capability of their membrane at 2000 but their support claims it has been tested only at 750ppm.
They also state they need 45psi at input for the membrane to work and for higher TDS the they recommend an in line booster pump for maybe higher psi.
I am also not seeing cutoff of the drain water though my storage tank is full. My whole house pressure pump is set at 42psi. I will increase this and see if it helps to reduce TDS and also stop the filtration or drain that is happening continously. If I cut off the input water for a minute or so, the drain stops and does not start till I consume some RO purified water from the storage tank.

[Miyata]

Originally Posted by diyguy

They also state they need 45psi at input for the membrane to work and for higher TDS the they recommend an in line booster pump for maybe higher psi.
I am also not seeing cutoff of the drain water though my storage tank is full.

Those two points could be related - after you've increased the pressure on the input side and it meets the required 45psi, it might resolve the issue on its own. A booster pump will do that too.

These units are certainly sensitive to pressure that way, cutoff valves etc. I am not sure, but most systems I've seen seem to allow for a provision to hack it for lower pressure applications as well.

If I cut off the input water for a minute or so, the drain stops and does not start till I consume some RO purified water from the storage tank.

Strange. If I understand this right, even in absence on any water inlet to the RO system, there is drain running if you lowered the water level in the storage tank?

If my understanding is right, your unit is then possibly trying to pull in residual water from the prior filters since it's still receiving a signal from the storage tank sensor unit. If true, it could damage the filters.

Instead of shutting off the inlet water, you could just power off the whole system and power back on when water is at say the half-way mark in storage?

[diyguy]

Originally Posted by Miyata

Those two points could be related - after you've increased the pressure on the input side and it meets the required 45psi, it might resolve the issue on its own. A booster pump will do that too.

Instead of shutting off the inlet water, you could just power off the whole system and power back on when water is at say the half-way mark in storage?

I diverted the water prior to the remineral filter and found the TDS to be 288 and after the mineralization it was around 306. I am not sure if this is safe to drink. Need to Google it a bit.
I haven't tried increasing the input water pressure as am being wary to other household connections. My sisters house has psi in excess of 60 while I have set it at 42 or so.

Powering off the unit will not stop the filtration as my unit works without power. It needs power only for the UV stage.

[Miyata]

I am a bit surprised to learn that. Hardly any 'effective' change in the TDS with or without re-mineralization - an average over time will possibly put them lot together and closer.

haven't tried increasing the input water pressure as am being wary to other household connections.

I was suggesting not to worry about the entire house, but just put in a booster pump local to the purifier. Depending on the age and condition of the pipelines running through the walls and floors, you don't want any unpleasant surprises as a consequence of pressure going too high everywhere!

[diyguy]

Originally Posted by Miyata

I am a bit surprised to learn that. Hardly any 'effective' change in the TDS.. M
... but just put in a booster pump local to the purifier

I found this link on TDS desirable levels.
https://buybestwaterpurifiers.in/dri...ter-tds-chart/
On the booster pump for the RO local, I found options on Amazon India claiming pressures of 90psi to 110psi. I plan to get one of them and try, any suggestions on the brand? I saw 24v and 48v ones and brands such as WELLON, AQ&Q, Eureka Forbes (rebranded) and Kent (rebranded).

[Miyata]

Originally Posted by diyguy

I found this link on TDS desirable levels.
found options on Amazon India claiming pressures of 90psi to 110psi. I plan to get one of them and try, any suggestions on the brand? I saw 24v and 48v ones and brands such as WELLON, AQ&Q, Eureka Forbes (rebranded) and Kent (rebranded).

The link appears to be among the more balanced ones and jibes well with my own R&D on the subject.

On the pump, I am not quite familiar with pros and cons on the brands. You could also check with the local water purifier chaps in the neighborhood stores as to what they use and how much they charge. The one I have (from kent) has been going good since the last 6-yrs.

[Adi22]

Hi All, any suggestions for a good choice of water purifier. Living in HSR Layout Bangalore, we get cauvery plus mix of borewell water. Which kind of purification is better , UV, RO.

Please advise.

[sgiitk]

@Adi22; If you are getting water from different sources, and must have no control where it is coming from, then RO is the safest. However, remember the TDS controller will not work. So might as well skip it.

[sagarpadaki]

Originally Posted by diyguy

I diverted the water prior to the remineral filter and found the TDS to be 288 and after the mineralization it was around 306. I am not sure if this is safe to drink. Need to Google it a bit.
I haven't tried increasing the input water pressure as am being wary to other household connections. My sisters house has psi in excess of 60 while I have set it at 42 or so.

Powering off the unit will not stop the filtration as my unit works without power. It needs power only for the UV stage.

Unless you are using common salt-based water softeners which need periodic re-filling the brine solution, the water from the softener is not fit for drinking. Such softeners that DO NOT use brine solution will neutralize the hard ions and make them inactive but does not remove the salts from the water. Hence the TDS does not reduce.

Any water with TDS less than 200 is fit for drinking.

[diyguy]

Originally Posted by sagarpadaki

Unless you are using common salt-based water softeners which need periodic re-filling the brine solution, the water from the softener is not fit for drinking.

I have just started using the 3M SFT 200 water softener that needs me to top up 50-60kg of crystal salt every month.

[civic-sense]

Originally Posted by civic-sense

That allays some fears. Any recommended brands/models? I saw a couple of them by Aquaguard, Kent and AO Smith. Am leaning towards Aquaguard as it appears compact. https://www.eurekaforbes.com/water-p...utc-ro-uv-mtds

After a long wait, finally got Aquaguard Invisipure UTC unit (https://www.eurekaforbes.com/water-p...-invisipure-ro) installed. The space below the sink was kind of cramped, so they had to make some modifications to the sink pipes to make room, but it was all handled by the installer, so I didn't have to call a separate plumber. They even drilled the hole in the granite to install the tap.

Output TDS is about 50, which seems a bit high considering the input water is just over 300. Not that it matters.

Our two whirlpool purifiers have always given me trouble. Hope Aquaguard turns out different.