[groundhog]

Following on from my previous thread regarding the enormous amount of resin I was getting through, now my membrane seem to have died!? It is a 20" HF5 and I have had it for less than 6 months! Surely it should last for longer than this? 

[martinw]

there is a number of things that could have happened to it. first of all whats your input and output tds from membrane?
what flow rate and pressure do you have there -lpm?
hf5  i had lasted nearly 2 years before i gave it away as it was only producing  towards the end 0.7 lpm at 16-20 tds from 350-400tds.

[Dave Willis]

If you remove it and turn the water back on you will know for sure?

[SB Cleaning]

Following on from my previous thread regarding the enormous amount of resin I was getting through, now my membrane seem to have died!? It is a 20" HF5 and I have had it for less than 6 months! Surely it should last for longer than this? 

Wasn't from the cleaning warehouse in wolves was it? As ive just had one go after 18 months last one lasted 3 years!!

[groundhog]

there is a number of things that could have happened to it. first of all whats your input and output tds from membrane?
what flow rate and pressure do you have there -lpm?
hf5  i had lasted nearly 2 years before i gave it away as it was only producing  towards the end 0.7 lpm at 16-20 tds from 350-400tds.

The input tds is 310, and it is coming out of RO at 137ppm. The water pressure is 45psi, and the flow rate is 1ltr in 8 minutes! Help!! 

[groundhog]

Following on from my previous thread regarding the enormous amount of resin I was getting through, now my membrane seem to have died!? It is a 20" HF5 and I have had it for less than 6 months! Surely it should last for longer than this? 

Wasn't from the cleaning warehouse in wolves was it? As ive just had one go after 18 months last one lasted 3 years!!

No it was from  Purefreedom 

[groundhog]

If you remove it and turn the water back on you will know for sure?

I removed it ealier and then refitted it and turned the water back on, but it is still the same. Is that what you mean?

[Dave Willis]

No, I meant that if the water flow shot up with no membrane at all then you'd know your water supply was ok and the membrane was deffo shot. I could be wrong of course.
Now you've given your readings it does look knackered to me.

[groundhog]

No, I meant that if the water flow shot up with no membrane at all then you'd know your water supply was ok and the membrane was deffo shot. I could be wrong of course.
Now you've given your readings it does look knackered to me.

Oh I see, I didn't think of that thanks! I think it is knackered though!    Has anyone else have a membrane go after such a short time? I'm wondering if there is some sought of warranty? Otherwise this is going to be expensive!! 

[Smurf]

I'm aware of Doug from Daqua mentioning he received similar phone calls that ro membranes brought elsewhere had clogged within 6 months.

You could always contact Doug directly for further advice

[martinw]

it seems clogged. to avoid it in the future the best is to have a flow of min 12lpm through the membrane.
regular prefilters change is a must with these. i know some here dont bother at all.

[groundhog]

it seems clogged. to avoid it in the future the best is to have a flow of min 12lpm through the membrane.
regular prefilters change is a must with these. i know some here dont bother at all.

How regular? I change mine whenever the tds creeps up too high. Is the 12lpm through the membrane include water to waste or just the water going through to the DI?

[Mick Kent]

45psi  simply isnt enough pressure which will cause problems, a hf5 needs around 80psi to run properly if i remember correctly.
I had the hf5 a few years back with 40psi before i got a booster pump and again lasted less than 6 months and was on 24/7 as took so long and the ppm was never lower than 30ppm as not wnough pressure running through. Now i use a hf4 with booster my membrane is 14 months old and from 360ppm in its comming out at 007-010 from ro before resin! Thats making 6000 litres of pure a week.
Mate you need a booster pump.

[Smurf]

I thought that pf 950 came with a booster pump?
http://www.purefreedom.co.uk/water-purification/950-gpd-high-volume-reverse-osmosis-system-20-membrane-20-hf4-with-large-booster-pump.html

[Dave Willis]

the way I read it - you have the choice to add  a booster pump at extra cost?

Not a criticism but I suppose if you are changing the prefilters when the tds has risen then it's too late - the damage has already been done to the membrane.

[martinw]

 min 12lpm  includes waste and pure altogether.
 what prefilters are you using as it all depends on them? how much water are you going through weekly/daily?
10 inch fibredyne  37.8k litres,20 inch  75k litres, 10inch jumbo 96k, other prefilters depends where you got them from.
booster pump would help to prolong the life as hf5 tends to clog up quicker than hf4. if you can afford it get hf4 with booster pump.  before you make you decision measure supply  water flow. if its too low, less than 12 lpm at 40-45psi  you may have to choose alternative slower ro.  you are not allowed to draw more than 12lpm using booster pump from mains.

[groundhog]

45psi  simply isnt enough pressure which will cause problems, a hf5 needs around 80psi to run properly if i remember correctly.
I had the hf5 a few years back with 40psi before i got a booster pump and again lasted less than 6 months and was on 24/7 as took so long and the ppm was never lower than 30ppm as not wnough pressure running through. Now i use a hf4 with booster my membrane is 14 months old and from 360ppm in its comming out at 007-010 from ro before resin! Thats making 6000 litres of pure a week.
Mate you need a booster pump.

I thought that the HF5 was designed to be used at lower pressures? I do have a booster pump, but I live in a very quiet rural area and the noise from the booster pump is just far too noisey to keep it on for prolonged periods!

[groundhog]

the way I read it - you have the choice to add  a booster pump at extra cost?

Not a criticism but I suppose if you are changing the prefilters when the tds has risen then it's too late - the damage has already been done to the membrane.

On my old ROman system I hardly ever needed to change filters, and when I did they were absolutely filthy!! But the membrane kept going for almost 8 years! When I change the filters on my 950 system they are still clean, but yet the membrane has had it after less than 6 months? 

[groundhog]

As my water pressure is quite low 45psi, does that mean I can turn off the flow to drain completely?

[groundhog]

min 12lpm  includes waste and pure altogether.
 what prefilters are you using as it all depends on them? how much water are you going through weekly/daily?
10 inch fibredyne  37.8k litres,20 inch  75k litres, 10inch jumbo 96k, other prefilters depends where you got them from.
booster pump would help to prolong the life as hf5 tends to clog up quicker than hf4. if you can afford it get hf4 with booster pump.  before you make you decision measure supply  water flow. if its too low, less than 12 lpm at 40-45psi  you may have to choose alternative slower ro.  you are not allowed to draw more than 12lpm using booster pump from mains.

I use 20" pre filters from Purefreedom, I have changed them about 4 times in the last 6 months. I will check to see what my lpm is. I thought that the hf5 was supposed to be used at lower pressures? I do have a booster pump, but it is too noisey to use in the quiet area I live in!