[Rich Wilts]

Ive had a 4040 R.O. unit for the last few years and have always struggled with producing clean water effectively and economically.

The unit never really seemed to produce at the volumes or quality that the manufacturers stated. My tap-water flucutaes but an average of 300 ppm is a reasonable figure that can be expected.

Out of the membrane I'd struggle to get it down to 40. I'd change pre-filters, suspect the membrane was shot for one reason or another, so have ended up buying new membranes every year. Until yesterday I was on my third membrane in 2 years.

Anyway, I had a chat with june at Gapswater and she suggested instead of the HF4 I go for the HF5 as they're better for lower pressure systems, my tap-water is 40 psi.

She supplied a new membrane at cost and I fitted it today. It started producing out of the membrane water at 13 ppm.

My resin consumption will go down by 2/3 rds, my water consumption should half. This all should mean I can stay in one of dazmonds chain of 5* hotels for Christmas this year  ;0

[Smudger]

If you use a booster pump you'd get it down to 5

Darran

[Rich Wilts]

Apparently the HF5 doesnt appreciate a booster pump. I would, to do away with resin, but according to June theyre not compatible.

[martin hulstone]

I had the same problem and the h5 got me own to around that figure, however within 6 months it had crept up to 40s again.  As smudger suggested a water pump is the best option. I have now had the same membrane for around 14 months and my tds is between 10 and 15 which is much better than it used to be, and it is much quicker at around 250 litres per hour

[Smudger]

I use hf5 membranes and boost the pressure to 80 psi, I get 005 out of them from 280 to 320 tds @ 150 litres per hour.

Although they are lower pressure than hf4 they are still more efficient at the 80 to 100 psi mark.

I get around 450,000 litres of pure before it creeps up, then It's usually knackered ie output is 20+ at the 600k mark

Darran

[Oliver @ GrippaTank]

I use hf5 membranes and boost the pressure to 80 psi, I get 005 out of them from 280 to 320 tds @ 150 litres per hour.

Although they are lower pressure than hf4 they are still more efficient at the 80 to 100 psi mark.

I get around 450,000 litres of pure before it creeps up, then It's usually knackered ie output is 20+ at the 600k mark

Darran

Darran makes a very good point.

Weather they are HF5 or HF4, each membrane has a sweet spot for the tds and flow output.

HF5 = 80 psi. Will work as low as 30psi but not as efficiently.
HF4 = 100 psi. Maintain this with the minimum flow rate and you will get a lower Tds reading.

[Rich Wilts]

I had the same problem and the h5 got me own to around that figure, however within 6 months it had crept up to 40s again.  As smudger suggested a water pump is the best option. I have now had the same membrane for around 14 months and my tds is between 10 and 15 which is much better than it used to be, and it is much quicker at around 250 litres per hour

So are you using a booster with an HF5 Martin?

[Rich Wilts]

I use hf5 membranes and boost the pressure to 80 psi, I get 005 out of them from 280 to 320 tds @ 150 litres per hour.

Although they are lower pressure than hf4 they are still more efficient at the 80 to 100 psi mark.

I get around 450,000 litres of pure before it creeps up, then It's usually knackered ie output is 20+ at the 600k mark

Darran

So spell it out for me Darren, you use an HF5 and a booster pump? I presume you use the Clarke cbm 240e?

[martin hulstone]

Yes, and you guessed it. The clarke 240e 

[Smudger]

Booster pump BUT NOT the Clarke pump, I have a dab pump been going 4 years without a hitch

It's the 82m
http://www.anglianpumping.com/products/dab-jet-pumps-230v ( I think )  APS picked the pump spec from my current water pressure and requirements these now come with a stainless steel chamber

Darran

[Rich Wilts]

Thankyou fellas!

[Walter Mitty]

I've never used an HF4.  My HF5 has been running for maybe 3+ years and still producing at 008 at 40PSI.  It is a bit low on production for such a membrane but it's plenty for a sole trader (about 1 to 1.5 litres of pure per minute).