[Gary Mabbott]

 Hi need advice
My water pressure is 45psi at 320 tds.
Mixed reports from differed suppliers!
What litre per hour could I expect to get without a pump?
Also need to have an auto stop but use half inch hose any advice appreciated.

[Shrek]

I spoke to pure freedom yesterday about this exact thing -
Hf5 on a 2400gpd without booster at 50psi , he said I’d easily get 1000ltrs a day

[p1w1]

Manufactures will give you the spec's at the perfect settings (perfect water temp, perfect pressure/ flow etc) which your not going to get in the real world. I would also guess by day they mean the whole 24 hours and not just your working day. Your production rate will be less in the colder months and get better as the weather heats up.

As mentioned in your other thread you can control the waste to pure but need to find the balance of making the pure water and getting the best out of your membrane.

Spruce has nearly the same tap pressure as you (but not sure what his tds is) and he gets around 2lt a min at 50/50 so i would go on the bases that your going to get around 2lt of pure a min so about 120lt an hour, and that sounds about right to me. You could have it making it quicker but the harder you work your membrane the quicker it's going to need replacing.

As for the auto stop this will do you http://gardinerpolesystems.co.uk/all-products/pump-hose/pump-controllers/system-controllers/liquid-logic-trade-autofill.html easy to set up and will do the job.

[Walter Mitty]

Hi need advice
My water pressure is 45psi at 320 tds.
Mixed reports from differed suppliers!
What litre per hour could I expect to get without a pump?
Also need to have an auto stop but use half inch hose any advice appreciated.

When my membrane was newish, at 40psi I got about one litre per minute, so around 1,400 litres a day (tap TDS around 200).  This would produce TDS from 000 to about 008 as it aged a little. This would drop a bit in winter.
These days it gives about 500 - 800 litres per day with an output TDS around 18 - 20.  No problem because it's still enough for me as a sole trader.  I can hardly complain as the membrane is about 8 or 9 years old, and it's only in the last 18 months that the depleted performance has become more noticeable.  OK, I need to buy resin a bit more often but even that isn't too great as I use two vessels behind the RO.  Vessel 1 is outputting around 003 right now so will climb to RO output level over the next three or four weeks (when I will change it), but the larger vessel (2) still has fairly fresh resin.

[Michael Peterson]

I easily get a 1000 literally a day similar set up to you

[Gary Mabbott]

Well, 2ltr per minute would be good as my Merlin gives me 500 in about 7 hours without a pump. Equates to 1.20 per minute in the winter &  summer nearer to 2 lpm. But tank TDS is always about 30 which I can handle as have 2 Di vessels to polish off. Get through a couple of Bags of resin a year, but for the amount of work we do isn't bad. The Merlin shuts off the pure via the ballcock in the tank but the waste doesn't shut off which is a common fault as they age. {Change my pre filter regularly)
It's a toss up between H5 4040 & a Merlin PRF.  From what Spruce has said I should get about 120 ltr an hour with the 4040 H5  at about 50/50  with 45 psi & 320TDS? Which would be a lot lass wasteful than my old Merlin.
Cheers for the advice lads, even an Old Guy like me still has lots to learn.

[mufcglen]

I’ve just installed an axeon hf5 and getting 3 litres pen min from 60/40 with 45-50psi tap pressure and tap ppm of 76, takes it down to about 4-5ppm

[Gary Mabbott]

Wow mufcglen  Thats pretty good 3ltr per minute would be great!

[Spruce]

Its all about water pressure. If you have low water pressure then throttling back the amount going to waste can help. But a lower water pressure than 50 psi will mean that the membrane won't quite work as efficiently as it would at a higher pressure. 50psi is the low end of the water pressure spectrum.

But in my expereience, my HF5 membrane is performing to spec so I personally can't see there being that much of a difference between 50 and 45psi. (If I have my r/o running and I turn on the outside tap the water pressure to the r/o will drop to around 40psi. Currently with a tap water tds of around 100 I've seen the output of my pure tds rise from 2 to 3ppm at 40 psi. For me the difference between the r/o working at 40psi and 50psi is negligible, for you it might mean the output difference of 3ppm. No one knows for sure.)

Your water tds is high at 320 so you might find your membranes longevity will suffer.
You just have to see if it works for you.

Nobody, and I mean nobody, will be able to tell you exactly how an HF5 membrane will work with your water pressure, your water temperature or the composition of the dissolved solids in your water.

.

[andyM]

It's a toss up between H5 4040 & a Merlin PRF. 

You already said that you are going on a water meter, so with the choice of a 4040 running at 50% waste or a Merlin PRF running at 75+% waste.
I know where my money would be going, and it wouldn't be down the drain.....