[dave0123]

how long should you run your pure water pipe to waste when fitted new filters?


is it best to run it flushing or just normal?

[dave0123]

anyone?

reason i ask  i have just changed my prefilters but the TDS is still sky high 29 atthe moment

[Alex Gardiner]

anyone?

reason i ask  i have just changed my prefilters but the TDS is still sky high 29 atthe moment

I would turn the valve to flush and let them run for about 1-2 hours.

[Peter Fogwill]

anyone?

reason i ask  i have just changed my prefilters but the TDS is still sky high 29 atthe moment

Dave it looks like you may need new membranes.

Peter

[[GQC] Tim]

I'm quite certain the pre filters do not come covered in any solution, you only need to flush the membranes through when they are new.

[dave0123]

well am flushing it now anyway as the other option isnt working so.

[dave0123]

Thanks Alex

[pjulk]

I just changed my prefilter today and put on flush for an hour.

TDS before DI was 012 but i expect that will come down to about 6 in a day or so usually does.

 

[dave0123]

Cheers paul will keep eye on it. So basicly they sort of settle in i spose?


goin to give it a good flush in the morning for few hours

[Peter Fogwill]

Dave what was the TDS just before the filter change?

Peter

[dave0123]

the TDS started to rise so they needed changing, before it was around 37 but in normal use it stays at 24.

iv only used the RO just hit three months and since the tds started to rise havent used WFP only using it on slected houses atm and leaded so havend made loads of water over the thre months peter.


dave

[Peter Fogwill]

Dave, is it a Merlin you are using?  If so it would account for the high readings, if not then it could be a dodgy membrane or two.  The readings are very high, and the membranes should last for years.

I take it you have a good flow coming from your waste?

The higher reading coming out the RO is associated with the membranes being on the way out and not the prefilters.  The prefilters are usually monitored with the pressure gauge, a drop in pressure = change the prefilters.

Peter

[dave0123]

Hi Peter,

No its not a merlin its 300GPD Purefreedom RO, there is good pressure when the booster pump is working its 84psi but only makes around 27-28 litres per hour. yes theres good flow cuming from the waste, dont know how much tho.

when  i changed these filters the pressure didnt rise again as if it dropped from the ones before. so do you think it could b a membrane? as i have never had the TDS out of the RO below 24 the tap tds is around 380 at the moment

[Peter Fogwill]

Hi Peter,

No its not a merlin its 300GPD Purefreedom RO, there is good pressure when the booster pump is working its 84psi but only makes around 27-28 litres per hour. yes theres good flow cuming from the waste, dont know how much tho.

when  i changed these filters the pressure didnt rise again as if it dropped from the ones before. so do you think it could b a membrane? as i have never had the TDS out of the RO below 24 the tap tds is around 380 at the moment

I would expect 8ppm at the very most coming from the RO with a tap reading of 380ppm, and a water pressure of 84psi, and I would expect at least 40L per minute at that pressure as well.  I am sure though that there was a post a few weeks ago regarding something similar, but I can't remember how it panned out, as I took a back seat as I was not familiar with the Purefreedom set up.

It could be a dodgy membrane, it has been know for them to not function properly from new.  I would test the water coming from each individual one to see if one has a much higher reading from the rest, and if so you can replace the faulty membrane.  It wouldn't do any harm to phone up the company with the readings you have, and see if they are normal.

Peter

[Alex Gardiner]

Hi Peter,

No its not a merlin its 300GPD Purefreedom RO, there is good pressure when the booster pump is working its 84psi but only makes around 27-28 litres per hour. yes theres good flow cuming from the waste, dont know how much tho.

when  i changed these filters the pressure didnt rise again as if it dropped from the ones before. so do you think it could b a membrane? as i have never had the TDS out of the RO below 24 the tap tds is around 380 at the moment

I've heard so many complaints about these RO's. It sounds like it's just a cheap chinese RO which just isn't up to much, with probably substandard membranes and filters. Replace them with american made Osmonics membranes and you should have no problems.

I would agree with Foxman (strange!) that it is best to stick to US made RO products as they are usually much higher quality and much more reliable.

[dave0123]

I did ring up purefreedom before.

i said to them my TDS after RO in normal operation before i had the rising tds was 24 and they said thats about normal for 380tds and they said 25 to 29 lit per hour is good and is what they get. i think the tds should be lower like peter said even 12 or 14 id be happy with.

anyway they said monitor it over the weekend so if it rises as it could just be a cold spell and if it remains the high tds they will sort it out.

but its actully warmed up here neally in t-shirt yestaday!!

[ would test the water coming from each individual one to see if one has a much higher reading from the rest/quote]

thanks peter i will try that in a bit.


where can you get new membranes from? iv tried lookin at Alex's site put can only see ones for a 4040 and a merlin i think.

[*foxman]

A decent 300GPD RO should be getting 380ppm down to 7-8ppm, at 24ppm I would say the membranes are on the way out.

As for 25 - 29 ltr per hour being 'good'....  25 - 29 ltrs per hour equates to around 670ltrs in 24 hours. A stated 300GPD RO being 'good' should be making around 1000ltrs each day no problem.

[Peter Fogwill]

I would also have to agree with Foxman, agreeing with me.

On a low pressure you would expect less than 300gpd, but with your pressure you should get at least, or more than 300gpd.  Did you tell the company that you were using a booster pump?

I had someones 300gpd system the other week and it produced just over 1L per minute, the water pressure was 140psi though.

Peter

[dave0123]

Yer i told them everything that i had a booster pump and the boosted pressure being 84psi

I said to them that i think its the membranes and i had some advice from you guys  because i have just replaced the prefilters yestaday. they must just be crap membranes as there only just hit three months old lol.

i will test the membranes like you said peter it has to be them? because theres nothing else left of the RO if not lol.

[Peter Fogwill]

Like I said I have come across faulty ones from new, and they have been filmtec membranes.  I have had problems with them as well when they used to come without being sealed in a bag, as they are not supposed to dry out.

Test them individually then you will know for sure.  Let us now how you get on.

Peter