[david mark]

My mains press is 4 bar t.d.s from tap is 126 pure water is 28 have new membrane and sediment and carbon filters any help thanks

[andyM]

If it's a new membrane then leave it flushing for a couple of hours and then adjust your waste valve to 50:50 and take another tds reading.
Is it a hf4 or hf5 membrane you have?

[david mark]

Hf4. I install it the wrong way then this moring had tds of 80 changed it round now down to 28 do you think ive damaged it

[andyM]

Do you have a booster pump?
I think 4 bar is roughly 55 psi and really the hf4 needs 100 psi to work effectively.

[david mark]

No dont have booster pump not sure what pump to get

[andyM]

Im just going from my own experience but I have around 35 psi tap pressure and when I got my hf4 I was only getting about 30ppm and pure output was slow from an input tap tds of 280ppm.
I bought a Clarke cbm 240e booster pump which got the water pressure up to 100 psi and now I get around 7ppm pure water output at about 250 litres per hour.
You might of been better off buying the hf5 membrane David as I think Spruce has a similar tap pressure and seems to get a decent out put from his from what I remember. 

[david mark]

Thanks for your help do you install the clark booster pump after the pre filters

[Spruce]

Im just going from my own experience but I have around 35 psi tap pressure and when I got my hf4 I was only getting about 30ppm and pure output was slow from an input tap tds of 280ppm.
I bought a Clarke cbm 240e booster pump which got the water pressure up to 100 psi and now I get around 7ppm pure water output at about 250 litres per hour.
You might of been better off buying the hf5 membrane David as I think Spruce has a similar tap pressure and seems to get a decent out put from his from what I remember.  

Hi Andy.

I think I would do as you suggested and buy an HF5 membrane. However, I would check first to ensure that the membrane has seated correctly in the housing.
I would have thought that the r/o would be more efficient than that. Also, are you sure your tds meter is accurate?
Can you find another local wfp cleaner who would counter-check the tds pure output for you.

Out tap tds is between 90 and 115 and the membrane gets the pure tds down to 2ppm. We get about 2LPM pure which is more than enough to keep the 3 of us going.

TBH I only flushed the new membrane for a couple of minutes before throttling the waste back and the output very quickly dropped to 2ppm - within a few minutes.

Once you start adding a booster pump then you have to add a controller to activate the water to the r/o when the IBC tank has water pumped out and switch everything off when the IBC tank is full. The Clarke pump has an electronic controller that will shut the pump down when the water is switched off.

see
http://www.cleanitup.co.uk/smf/index.php?topic=168920.0

[Spruce]

Thanks for your help do you install the clark booster pump after the pre filters

Most usual is after prefilters and before membrane. I'm sure someone will suggest the correct hose to use that will take the increased pressure.

If you do a search there were a couple of posts a few years ago on the fittings you will require on the booster pump to get you going.

[david mark]

I have 2 t d s metres both show same reading im running 2 merlin ro and getting 2 ppm from each of them but it takes a long time to fill 3x I b c tankes I purchased the 40-40 membrane housing as a used item but the membrane is new from gaps water maybe the small 2 o rings are worn on the in and out ports.Drilled a 1mm hole in gate valve but can't get it lower than 28 ppm

[Spruce]

I have 2 t d s metres both show same reading im running 2 merlin ro and getting 2 ppm from each of them but it takes a long time to fill 3x I b c tankes I purchased the 40-40 membrane housing as a used item but the membrane is new from gaps water maybe the small 2 o rings are worn on the in and out ports.Drilled a 1mm hole in gate valve but can't get it lower than 28 ppm

The gate valve mustn't be closed - the 1mm hole I drilled was for safety. I still have the valve open a bit. Using my hf5 membrane I have a 2lpm waste to 2lpm pure ratio and that gives me the best output.

If the waste is open any more than that the tds of the pure goes up and the quantity produced drops.

[andyM]

Thanks for your help do you install the clark booster pump after the pre filters

Before pre-filters or before membrane, it doesn't make any odds.
Mine is installed before the pre-filter and the pressure gauge still reads 100 psi before the membrane.
I use a single Fibredyne cfb-plus pre-filter and so there doesn't seem to be any noticeable pressure drop.

[david mark]

Thank you for your input and time in helping me Andy Spruce. Will let you no how I get on