[Mick Kent]

And cheaper too...For the last 2 years i have bought 2 hf5 membranes which didnt get my water below 30ppm and crept up every few months to in the 40's which realy annoyed me, just checked my tds meter now after having the hf4 for a week and water is coming out at 005 from 360 in.
All it consists of is a pure freedom 4040, an 80 psi booster pump. I changed the valve also and am pureing at roughly 70/30.
Im a happy man as never had it so low.. A sack of Resin should now last a few years instead of a few months fingers crossed.

[andyM]

Yes you should notice a significant saving in resin use.
A 70/30 ratio is probably the kindest to the membrane if you are in a hard water area and if you are not on a water meter the amount of waste water won't matter to you.
I run mine on 60/40 because I have a metered supply.
You do need to change your filters regularly though, as the membranes won't tolerate chlorine and at £250 a pop membranes aren't cheap to replace. I mention this as you say you have had 2 in 2 years.
An adjustable waste valve is an absolute must and im surprised you didn't fit one sooner?   

[Mick Kent]

To be honest i didnt realise the adjustable waste valve would make such a difference, i assumed pure freedom would have had the correct fitting on there equipment.
I normally change filters every 2/3 months but will now do it monthly to keep it as low as it is.

[David Kent @ KentKleen]

Mick, how many litres an hour or day is it producing at the moment? The cold weather is slowing my production down drastically. I don't use a hf4 but may look at buying one. Thanks in advance

[Mick Kent]

Doing 2000 litres in just over 8 hours give or take. I cant work out why its in a different league to the hf5 and is less money! Maybe the valve played a big part.. Oh well at least no more throwing money at resin every 2 months.

[David Kent @ KentKleen]

Thanks Mick, will get one ordered.

[Scrimble]

I am disappointed with my hf4 from pure freedom, I currently get 22ppm at about 85psi no booster pump its only 6 months old it has crept up from 14ppm already and I change the pre filters every 2 months and flush for 5-10 mins before every use

before I had a 450gpd ro which after 4 years of use was putting out 14-15ppm

[Mick Kent]

Whats yours before ro though scrimble??
At 22 id still be happy.

[Spruce]

I think PF will always recommend you use an HF4 when your system is fitted with a booster pump. They did to me.

[Scrimble]

I think PF will always recommend you use an HF4 when your system is fitted with a booster pump. They did to me.

my ppm out the tap is around 270,

spruce I used to use a booster pump which took it to around 90psi, at my unit the water pressure is 85psi so I dont bother using it  there is no need