[ftp]

http://www.gapswater.co.uk/acatalog/copy_of_Reverse_osmosis_kits.html

What does it mean when you have a 98% rejection rate? Does it mean that 2% goes down the drain?

[Window Washers]

http://www.gapswater.co.uk/acatalog/copy_of_Reverse_osmosis_kits.html

What does it mean when you have a 98% rejection rate? Does it mean that 2% goes down the drain?

rejects 98% of impurities, if only 2% went down the drain I would be calling them in the morning and buying another 2 4040's. sadly I will not be calling them as this is yet to be on the market

[ftp]

Bit miss-leading the way they advertise that. Surely all ro's would have a similar 98% rejection rate?

......... so which ro's have the lowest rejection in terms of waste water apart from fancy Ionics ones?

[matt]

you still worried about your new house and the water meter

its tax deductable you know

[ftp]

  Don't know yet. Me and the wife will have to shower at the Gym, kids will be washed at the public toilets.

[leapstallbuildings]

Bit miss-leading the way they advertise that. Surely all ro's would have a similar 98% rejection rate?

......... so which ro's have the lowest rejection in terms of waste water apart from fancy Ionics ones?

No.  Rejection rates can vary quite a bit.  Merlins aren't particularly clean ROs.  . especially one the membranes have been in a while.  Even with fairly new membranes I have a posat RO TDS of 016 compared to about 200 TDS from tap.  Also, the water pressure going into the RO can make quite a difference.  Local conditions such as tap TDS, water pressure into RO, the type of RO can all make a difference.  Also, sometimes an RO may be setup so that the ratios can be changed manually.  For instance, if someone needs a load of water in a hurry, they may have it set up to temporarily restrict the waste water.  This will give a higher TDS post RO but this may be the lesser evil if it's quantity that's needed.  Obviously it will probably need to go through some resin before use though.

[mark dew]

http://www.gapswater.co.uk/acatalog/copy_of_Reverse_osmosis_kits.html

What does it mean when you have a 98% rejection rate? Does it mean that 2% goes down the drain?

98% rejection rate. It means it rejects 98% of the water.
Don't sound right though. If 1000 litres of water is a quid on the meter, 1000litres of pure water would cost £50.

[Niall McAllister]

you want to start rainwater harvesting

[cybersye]

http://www.gapswater.co.uk/acatalog/copy_of_Reverse_osmosis_kits.html

What does it mean when you have a 98% rejection rate? Does it mean that 2% goes down the drain?

98% rejection rate. It means it rejects 98% of the water.
Don't sound right though. If 1000 litres of water is a quid on the meter, 1000litres of pure water would cost £50.

no its as window washers says, it rejects up to 98 % of the tds, not the water.
I have an hf5 4040 membrane from gaps, you can tweak the waste/pure ratio by means of a tap, have mine set up to produce about half as waste.
My supply tds is about 360 ppm and the product after ro is about 8-10 ppm, so not far off a 98 % rejection rate .
Used to a have a merlin and set up under same conditions, getting on for nearly 75 % water went to waste and had a product of 40 ppm ( 4 times that of the hf5 ) giving a rejection rate just less than 90 %.

[cybersye]

http://www.gapswater.co.uk/acatalog/copy_of_Reverse_osmosis_kits.html

What does it mean when you have a 98% rejection rate? Does it mean that 2% goes down the drain?

rejects 98% of impurities, if only 2% went down the drain I would be calling them in the morning and buying another 2 4040's. sadly I will not be calling them as this is yet to be on the market

Do you run 2 hf5 membranes window washers ?
If so is it twice as good as one ? I mean does it half the product tds  and the waste again and produce twice as much water ?

Being in a flat and on a meter, I may consider upgrading to 2 hf5's if this were the case.
Thanks
Simon