RO system query - mechanical
Moderators: B.Scott, vippymini, Gazza, Manky Sanke
Gazza, I assume you meant 1000ml? (jug)
My system is in the filter house which is brick built, pipe runs are a few meters for mains, run in plastic at 2m height for better heat retention.
Jane, the calc is nigh perfect as you present it, even going the extra decimal place only takes it to 177.6 gpd.
So, it seems I may have a problem, lets analyse the possibilities.
I have just checked my system operating conditions, input water temp is 7.7 degrees, pressure is 90 psi.
Applying the manufacturers formulae to these figures, the system should produce around 112 gpd with water at this temp and pressure of 100 psi min. My pressure is 90 psi, so 10% minus would leave 100 gpd. These are accurate figures using the makers provided formulae, you will see I hope why I am questioning your readings Gazza.
The above was derived using the following math:
Membranes x 3, each rated at 80 gpd (UK) at optimum conditions, which are stated as:
Temp 25c
Pressure 100 psi min.
My temp is 7.7 so Temp correction factor as provided by manufacturer is 2.14
So, 80 (UK gpd) divided by 2.14 = 37.38 per membrane, x3 = 112.14 gpd total for the system which has 3 membranes. Less the 10% for pressure drop = 100 gpd. I am only getting 60 ish so obviously all is not well.
It could be the alternative cartridges currently in use are restrictive, so I have just ordered 2 sets of the original replacement cartridges, we'll see what happens then.
To achieve the (clarified) 180 gpd your water would have to be very warm Gazza, based on spec's your input water woulfd have to be 17c, and that's assuming pressure is 100 psi, higher if not!
Jane, if there's one thing sure to pee a fellow off it's a woman with a good idea, a woman with a cracking idea is anathema! (heating tape)
Chi
My system is in the filter house which is brick built, pipe runs are a few meters for mains, run in plastic at 2m height for better heat retention.
Jane, the calc is nigh perfect as you present it, even going the extra decimal place only takes it to 177.6 gpd.
So, it seems I may have a problem, lets analyse the possibilities.
I have just checked my system operating conditions, input water temp is 7.7 degrees, pressure is 90 psi.
Applying the manufacturers formulae to these figures, the system should produce around 112 gpd with water at this temp and pressure of 100 psi min. My pressure is 90 psi, so 10% minus would leave 100 gpd. These are accurate figures using the makers provided formulae, you will see I hope why I am questioning your readings Gazza.
The above was derived using the following math:
Membranes x 3, each rated at 80 gpd (UK) at optimum conditions, which are stated as:
Temp 25c
Pressure 100 psi min.
My temp is 7.7 so Temp correction factor as provided by manufacturer is 2.14
So, 80 (UK gpd) divided by 2.14 = 37.38 per membrane, x3 = 112.14 gpd total for the system which has 3 membranes. Less the 10% for pressure drop = 100 gpd. I am only getting 60 ish so obviously all is not well.
It could be the alternative cartridges currently in use are restrictive, so I have just ordered 2 sets of the original replacement cartridges, we'll see what happens then.
To achieve the (clarified) 180 gpd your water would have to be very warm Gazza, based on spec's your input water woulfd have to be 17c, and that's assuming pressure is 100 psi, higher if not!
Jane, if there's one thing sure to pee a fellow off it's a woman with a good idea, a woman with a cracking idea is anathema! (heating tape)
Chi
According to the supplier the sed's are 5 micron, same as original.
I will wait and see if the replacement original cart's improve anything before panicking!
It's just that by any reasonable calculation it's highly improbable gazza could be getting 180 gpd, unless his input water is 17c or higher, so that mystery added to my current problem is enough for one day!
I'm off to investigate tape heaters!!
Chi
I will wait and see if the replacement original cart's improve anything before panicking!
It's just that by any reasonable calculation it's highly improbable gazza could be getting 180 gpd, unless his input water is 17c or higher, so that mystery added to my current problem is enough for one day!
I'm off to investigate tape heaters!!
Chi
Chi/ Jane
Touched on this on the old board
Its kind of possable to recyle pond water. As part of an experiment I set up one of the ro-mans water pumps and left it running through the 5 micron sediment filters, with water extracted from the pond, however due to work commitments I had to stop after 5 days , but with a water meter on the end there was no noticeable decline in water volume being pushed through.
Cant remember the exact figures but it was enough to take the experiment and to the next level and attach RO unit, however the extra pressure of the membranes/ length of pipe involved caused the pump to cycle (ie create pulse's rather than a constant flow) been waiting to speak to some of the pump vendors in the know at work???? , but my thoughts are that I need a bigger water feed to the pump, as I feel their wasnt enough water available for the pump to do it stuff, as I feel it may have been cavitating .
One concern I do have though is that from pond water there are live organisms, in the water supply which may/will contaminate the membrane. My next trip down to Bristol will hopefully allow me to have a closer look at maurices system as he is using groundwater as his supply
One thing to bear in mind is that sediment filters are a couple of quid and a metre of water is £1.50. So even a couple of "free" cubic meters would cover the cost of the sediment filters
Economically its worth it, the areas where the problems need to be addressed are the development of a pump system that wont pulsate and does the water needs to be passed through a heavy duty UV to kill anything in it.
Chi - look forward to your contribution, but may be a wee while before I can respond
Chester
Touched on this on the old board
![Idea :idea:](./images/smilies/icon_idea.gif)
Its kind of possable to recyle pond water. As part of an experiment I set up one of the ro-mans water pumps and left it running through the 5 micron sediment filters, with water extracted from the pond, however due to work commitments I had to stop after 5 days , but with a water meter on the end there was no noticeable decline in water volume being pushed through.
Cant remember the exact figures but it was enough to take the experiment and to the next level and attach RO unit, however the extra pressure of the membranes/ length of pipe involved caused the pump to cycle (ie create pulse's rather than a constant flow) been waiting to speak to some of the pump vendors in the know at work???? , but my thoughts are that I need a bigger water feed to the pump, as I feel their wasnt enough water available for the pump to do it stuff, as I feel it may have been cavitating .
One concern I do have though is that from pond water there are live organisms, in the water supply which may/will contaminate the membrane. My next trip down to Bristol will hopefully allow me to have a closer look at maurices system as he is using groundwater as his supply
One thing to bear in mind is that sediment filters are a couple of quid and a metre of water is £1.50. So even a couple of "free" cubic meters would cover the cost of the sediment filters
![Exclamation :!:](./images/smilies/icon_exclaim.gif)
Economically its worth it, the areas where the problems need to be addressed are the development of a pump system that wont pulsate and does the water needs to be passed through a heavy duty UV to kill anything in it.
Chi - look forward to your contribution, but may be a wee while before I can respond
Chester
Incidentally Gazza and all, one of the carbon cartridges I am currently using is half the price of the equivalent from RO man. But, I notice that the design is considerably different, instead of a flow through casing it has a flow down design with a solid casing. Water enters at one end and exits at the other, which offers a much reduced path area, and I think flow is going to be commensurate. This may explain the poor output, we'll see when I get the others fitted.
Chi
Chi
Hi Gazza, mad? I know not but I doubt it, but I'm sure you can see where I'm coming from. Your system is producing more output than the manufacturer claims possible at anything remotely resembling current temps and water pressures. On the other hand, a simple measuring jug can't lie, can it?!!!
I've ordered 2 of those slim inline digital units from RO man, these monitor flow and cartridge condition etc:
http://www.ro-man.com/shop/product_info.php ... cts_id=102
I've also ordered some small quick fit none return valves which are new stock, I hope to deploy these to stop the ruddy water going everywhere when changing cartridges!
He claims that when running properly the system I have should run at or around 1 to 1 product to waste ratio, mine's a little higher than that I think. The meters also monitor cartridge usage/life so that'll finish the job off nicely.
Which reminds me gazza, which flow restrictor are you using? That's the little round white cylinder about 12cm x 2cm, usually hidden behind the bottom RO cartridge. There are identifying numbers on them, I'm just looking at all possibilities for your incredible production rate.
Chi
I've ordered 2 of those slim inline digital units from RO man, these monitor flow and cartridge condition etc:
http://www.ro-man.com/shop/product_info.php ... cts_id=102
I've also ordered some small quick fit none return valves which are new stock, I hope to deploy these to stop the ruddy water going everywhere when changing cartridges!
He claims that when running properly the system I have should run at or around 1 to 1 product to waste ratio, mine's a little higher than that I think. The meters also monitor cartridge usage/life so that'll finish the job off nicely.
Which reminds me gazza, which flow restrictor are you using? That's the little round white cylinder about 12cm x 2cm, usually hidden behind the bottom RO cartridge. There are identifying numbers on them, I'm just looking at all possibilities for your incredible production rate.
Chi