Jump to content
Sign in to follow this  

Elite Window Cleaning 83

Recommended Posts


Hi Guys, so I am new to wfp and I need some advice on the waste gate valve on my static system. I have a pure freedom ro system but am I struggling to work out the correct waste/pure ratio. Please help. Cheers 

Share this post

Link to post
Posted (edited)

There is lots on this site regarding pure to waste ratios.


With a lower tap water tds (150ppm) my 4040 performs best with a pure to waste ratio off 55% waste to 45% pure with my water pressure.


However, if your taps water tds is high then you could be looking at 2 waste to 1 pure (ie 2 liters of waste to 1 liter of pure.)


My advise is to get it working at around 2 to 1 and then take tds readings for your r/o pure outlet as you slowly close the waste gate. But never go less than 1 waste to 1 pure. Each time you make an adjustment you need to wait a few minutes to let the r/o settle.


The easiest way is to run the pure into 1 x 20 liter container and run the waste into another next to it. You should get an idea of which way to go by comparing the two levels. You may run into difficulties with trying to get this right though. For example, Pure Freedom drill a hole though the paddle of their gate valve so its impossible to shut the waste off completely and damage the membrane. Unfortunately that hole will give between 2 and 3 liters of waste to 1 liter of pure. Many years ago Merlins were set to a 5 to 1 ratio.


I drilled a much smaller hole through my gate valve paddle, but over time that hole has worn bigger.

Edited by spruce

Share this post

Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.