[Alistair@AWC]

Hi Guys,

Just after a bit of advice ive just set up my WFP system to produce water!

My water was showing approx 150ppm from the tap then when its gone through the Merlin it was showing approx 15ppm and then it went through my 700ml DI canister (which was bought prefilled from Gardiners) and was showing 0ppm all great upto now...............but after approx 900 litres of pure water the DI canister was producing water at 4ppm

Surely the resin is supposed to last longer than that, as Gardiners site says 1 litre should last a w/c approx 4/6 months

Any ideas would be appreciated

Regards Alistair

[Extremeclean]

You need your change your resin quickly.

At 15PPM you will go through 700ml of resin every 900 to 1000ltrs.

If you use the equation of 500000 divided by the TDS in for pure water produced per 25ltrs of resin you get a figure of 933 litres of pure per 700ml of resin at 15PPM in.

I havent seen what you say is on the Gardiner site but if it's there it really shouldn't be. I am sure if you point this out to Gardiners they will sort it out though. No-one can ever say how long X amount of resin will last all window cleaners. There are far too many variables to consider.

[Alistair@AWC]

Thanks Extreme,

So do you think there could be a problem with my Merlin RO if its allowing 15ppm through

OR

Is there any other filter type thing that I can fit to my system to bring the TDS down a bit more before it gets to the DI vessel because I dont fancy having to change it every time I fill my IBC


Thanks

Alistair

[Extremeclean]

I suspect you probably have low water pressure.

You could fit a booster pump for the Merlin. Your TDS out figure is 90% of in so boosting should help. You can fit a sediment filter and perhaps a carbon filter before the Merlin but it wont really make much difference to your TDS out.You really need 60PSI plus of water pressure for the merlin to work better at reducing TDS. I have a couple and have booster pumps on both of them and get 97% TDS removal.

I wouldn't bother with a silly 700ml DI vessel if you are using a Merlin and quite a bit of water.  You will be changing your resin far too often and run the risk of high TDS out of the whole system. You would do better with say a 18 x 6 inch DI vessel. One benefit is that it is small enough take with you and top up if you need to. It all depends on your needs really.

[Alex Gardiner]

Hi Alistair,

I have been looking through our printed material and on our website and cannot find the recommendation that the 700ml canister should last 4-6 months, the only recommendation we make for resin canisters is:

 "Resin bead change is the final stage in the unit and this will need changing whenever your output TDS reading rises above 000-001ppm"

However the post resin stage on the 200gpd units we supply should well only use 1 litre every 4-6 months.

Looking at your situation it does look like you have low water pressure, as has been said, the only cure for this is to fit a booster pump. You have to be careful which pump you use as many of the off-the-shelf Merlin booster pumps are useless and can burn out in just an hour, they are designed for drinking water use only. We can supply a variable rate booster pump which will deliver up to 70 lpm of water at a good pressure.

The other solution, as has been said, is to fit a larger resin bead canister, we have a good deal on the 14litre size at the moment.

Any other problems give us a ring

Alex Gardiner

[Alistair@AWC]

Hi Alex,

Could you let me know how much the 14 Litre DI canister is?

Regards

Alistair

[Alex Gardiner]

I will get Kirsty to ring you with a price.

Alex Gardiner