Tds reading 17

[gaz]

Everything is the same old ones read 5, new ones read 18. I won't get a refund if they read 18, I'll check see if 1 is faulty. I'll flog em on eBay

 

[doug atkinson]

Gaz take a reading from each membrane. You may find one is at fault

 

[gaz]

Shall I keep the 2 in what read 5 and test the 3 new ones as as unit of 3 where only one is a new one? Or shall I just test 1 new one and leave other 2 housings empty?

 

[doug atkinson]

Shall I keep the 2 in what read 5 and test the 3 new ones as as unit of 3 where only one is a new one? Or shall I just test 1 new one and leave other 2 housings empty?

I presume you put in 3 new membranes and got a reading of 18 from all 3.

If so then put all three in, flush the system for about 15 mins the close the flush. Disconnect the pure hose going into the T Piece which you then should be able to take a reading from all 3 membranes.

 

[gaz]

My tds reader died on me, awaiting new one tomorrow I'll update u what happens, bit unsure how to test each membrane so gunna leave 2 old membranes In and keep swapping the 3Rd with a new membrane see if the 3 overall readings are different. Example I get 5 another 5 then a 20 then I know it's the 3Rd one what's problem

 

[Iurie]

The ones reading 5 are too slow so I bought new ones and that way my old ones can be used for an emergency set

May I ask you - if you see any visual difference between 150 GPD membrane and your old one ? I mean they look the same , weigh the same , same size ...

Usually I get 75 or 100 gpd and can't see any difference visually or in the amount of water they produce

 

[spruce]

Shall I keep the 2 in what read 5 and test the 3 new ones as as unit of 3 where only one is a new one? Or shall I just test 1 new one and leave other 2 housings empty?

No, as Doug says, put all the new membranes in, flush your system and then run it as normal for about 5 minutes. You will see all the pure pipes are joined together before they head off to your di/storage tank.

Each of those pure pipes will be joined together with a JG T piece. You will be able to remove each pipe from each housing and collect a pure sample from each. Collect a sample from membrane no1 and then test it. Collect a sample from membrane no2 and then test that. Do the same with membrane no3.

With those readings you should be able to identify if you have a 'faulty' membrane and which one it is.

 

[spruce]

May I ask you - if you see any visual difference between 150 GPD membrane and your old one ? I mean they look the same , weigh the same , same size ...
Usually I get 75 or 100 gpd and can't see any difference visually or in the amount of water they produce

There's a size difference between the 75GPD membranes we removed from our r.o many years ago and the 150's we replaced them with. The 150GPD were a bigger diamt.

 

[gaz]

Right guys 3 old ones read 5 or 6, very slow. I tested 1 new one with 2 old ones, the reading on 3 separate occasions with the 3 different new membranes was 9. So it seems there is no dodgy one. I then retested the 3 new ones all together and it now reads 11 not 17 and above ad it did other day, I am now happy with this reading, they are much faster.

In regards to comparisons between 100gpd membrane and 150gpd membranes I've had both in past, both same size physically and I'm not sure if I got any more water production from the 150s, I couldn't tell really, next time I'm getting 100gpd as my unit is off at times

 

[spruce]

Right guys 3 old ones read 5 or 6, very slow. I tested 1 new one with 2 old ones, the reading on 3 separate occasions with the 3 different new membranes was 9. So it seems there is no dodgy one. I then retested the 3 new ones all together and it now reads 11 not 17 and above ad it did other day, I am now happy with this reading, they are much faster.In regards to comparisons between 100gpd membrane and 150gpd membranes I've had both in past, both same size physically and I'm not sure if I got any more water production from the 150s, I couldn't tell really, next time I'm getting 100gpd as my unit is off at times

I think its very difficult to tell tbh. All I know is that they were not as slow to fill the IBC tank than the 75GPD ones were. But we didn't have the 75GPD ones in long enough to draw any comparison facts over a period of time.

 

[Dave B]

Surely the lower the gpd membranes the more waste you get as the water can't push through as quick

 

[David K]

I Can go for ages without changing my 11l DI vessel, and i have about 15 ppm from RO unit . Maybe even 6 months.

 

[David K]

I Can go for ages without changing my 11l DI vessel, and i have about 15 ppm from RO unit . Maybe even 6 months.

 

[gaz]

Just to let people know my 450gpd new membranes produced 750 litres in 24 hours. 450 gallon is 2045 litres, so rhe membranes don't do what they say on the tin lol

 

[Dave B]

The figures quoted are for optimum conditions

Perfect water pressure, water temperature etc

Especially in the winter temperatures it wil be a lot slower

 

[spruce]

Just to let people know my 450gpd new membranes produced 750 litres in 24 hours. 450 gallon is 2045 litres, so rhe membranes don't do what they say on the tin lol

As per @daveyboy.

Also the spec per day = 24 hours and the gallons are US gallons which are about 4 liters.

Yours is doing better than ours did. It took about 28 hours in winter to fill an IBC tank with a little water in the bottom that couldn't be sucked out with the transfer pump. So estimated that it would take 36 hours in the winter to fill it from empty.

This is why I believe that the bare minimum for a single cleaner is a 300 GPD and that would probably run near enough all day and all night keeping up with daily usage. A 450GPD will give a single operator enough water with a bit to spare.

We struggled with 2 cleaners and our 450GPD r/o.

.

 

[spruce]

Surely the lower the gpd membranes the more waste you get as the water can't push through as quick

Not necessarily. You buy a waste restrictor to suit the membranes you have.

So the restrictor for a 50GPD membrane will have a smaller orifice than the restrictor for a 150GPD membrane.

 

[gaz]

I got 2 ibc tanks, when 1s full I pump the other full with a hippo water pump in each tank. Also got a 2nd ro unit at my nans house with 1 ibc tank too. Got 4 workers. Its good to have more than 1 unit for emergencies