Clean It Up

UK Window Cleaning Forum => Window Cleaning Forum => Topic started by: drevitt on December 10, 2007, 07:57:15 pm

Title: Twin DI Vessels
Post by: drevitt on December 10, 2007, 07:57:15 pm
I was using a 200GPD RO unit then onto DI Vessel but used a lot of resin, was advised to poss set up water to go through RO unit then two DI Vessells (through one, 30cm hose then through other) I find that the Resin on the second vessell lasts a bit longer than before (approx 4 days) but when I check the first vessell the water runs through the ppm reading takes about 2 weeks to change, does anyone else know anything about this and if it is not going through the first vessell properly ?

thanks
Dave
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 08:58:13 pm
I keep it till it goes to about 10ppm but why does the reading from the second DI vessell seem to go up quicker than the first vessell ? cheers
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 09:30:38 pm
no. I change to resin when vessel 2 goes up to 002 ppm, but just cant figure out why if water is going through first vessel, coming out at only 002ppm then goes into 2nd vessel why does second vessel reading go up quicker than first vessel ???
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 09:38:20 pm
hand held tds, is there a method to set it up as its almost as if it is missing out the first vessel
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 09:48:23 pm
yes the other day vessel 1 = 2ppm    vessel 2 = 0ppm

                   today vessel 1 = 2ppm    vessel 2 = 2ppm

confusing hey ?
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 09:55:09 pm
20ppm but goes up to approx 60 after an hour or two I think ?
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 09:55:51 pm
then I flush system out till back down to 20ppm or less
Title: Re: Twin DI Vessels
Post by: Nathanael Jones on December 10, 2007, 09:56:48 pm
60ppm out of your RO???

What's the input TDS???

60ppm is very high,... a booster pump would probably be a good investment.
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 09:59:35 pm
only had it a month or so ?
Title: Re: Twin DI Vessels
Post by: Nathanael Jones on December 10, 2007, 10:02:26 pm
Are you using the 10" vessels that only hold 700ml resin???
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 10:03:16 pm
yep, also tap water very hard 400ppm approx
Title: Re: Twin DI Vessels
Post by: Nathanael Jones on December 10, 2007, 10:06:24 pm
Those little vessels are the same size as the RO pre-filters right? They're much too small if you water is that hard. I'd recommend using 2 6litre vessels at least,.. 11litre might even be a good idea.

Even so, your RO should be reducing the TDS further. What's your tap pressure?
Title: Re: Twin DI Vessels
Post by: drevitt on December 10, 2007, 10:07:50 pm
are 6 litre and 11 litre expensive

dont know tap pressure, all quite new to me WFP
Title: Re: Twin DI Vessels
Post by: Nathanael Jones on December 10, 2007, 10:14:59 pm
http://cgi.ebay.ie/ws/eBayISAPI.dll?ViewItem&rd=1&item=150193353077&ssPageName=STRK:MEWA:VRI

2nd hand, but still good and very cheap.

They're the same price whatever size you get,.. so its just down to how much you want to spend on resin filling them up the first time!
Title: Re: Twin DI Vessels
Post by: Nathanael Jones on December 10, 2007, 10:18:43 pm
Here's a pressure gauge too:
http://www.ro-man.com/shop/product_info.php/cPath/23/products_id/76

If you're below 40 PSI then your filter won't perform great. Up the pressure any you'll get more water AND a lower TDS after the RO membrane. RO-man sell booster pumps fairly cheap too.