DI Vessel not performing as expected

Fudger

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Chaps, bought a DI Vessel recently but I am struggling to get the PPM down to anywhere near zero.

My tap PPM is 299 and I can get it down to the 70's when using the vessel. Should I be happy or disappointed with that? If disapointed, what am I doing wrong and/or are there any tips?

Many thanks.

The vessel is 11.7 litres pre-filled with MB-115 DI resin
 

Litcan91

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Apparently, if it's new, they don't give out 0ppm straight away and it should improve.
 

st13phil

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Something isn't right. Straight from the tap my TDS-3 reads up to 325ppm, but my DI Vessel will give 0ppm immediately after refilling with Tulsion MB-115 resin.

A few things:
  1. Is the DI Vessel connected the right way round (obvious question, but needs to be asked)?
  2. Was the DI Vessel supplied pre-filled with resin, or have you filled it? If the latter, did you put enough resin in?
  3. Are you sampling the water straight out of the DI Vessel, or at the end of a connected hose? If it's at the end of the (previously used) hose remember that it will take some time to flush through anything that the hose has previously "picked up" on its inner bore.
  4. What's the flow rate? If you have very high mains pressure and run it flat out through the DI Vessel you can get a flow rate that exceeds the capability of the resin. Slow the flow and see if the TDS level improves. By running my vessel open to atmosphere with the tap full open I can get 10-15ppm even on new resin, but at the end of the hose with a trigger spray head reducing the flow it's 0ppm again.
FWIW, I find that anything over 25-30ppm results in spotting on the car, so you need to work out what's going on and fix it.

Edit: Sorry, just re-read your post and saw that you'd already answered point #2. If you bought it from Daqua, and none of the above works, perhaps it's worth giving them a call?
 
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developer

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Something isn't right. Straight from the tap my TDS-3 reads up to 325ppm, but my DI Vessel will give 0ppm immediately after refilling with Tulsion MB-115 resin.
Mine too - and after a resin change.

After following Phil's excellent advice above, I too would be contacting the supplier.

I wonder if the resin has "gone off" - old stock perhaps?
 
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Fudger

Fudger

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Gents, I feel completely embarrassed to say that after I checked Phil's first piece of advice I found that the vessel was connected the wrong way round.

I know what happened: I had a slight leak from one of the connectors and had to add a little more PTFE tape. Whilst reconnecting, and after being interrupted by the boss, read wife, I reconnected the vessel the wrong way round.

Anyway, I now have a reading of 001 PPM which is brill.

Sorry to have wasted your time chaps :eek:

Jonathan
 
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Fudger

Fudger

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A result indeed. I have now rinsed the car down and there are zero water spots developing :D

However, I wish I knew about DI Vessels 25 years ago :wallbash:
 

st13phil

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Anyway, I now have a reading of 001 PPM which is brill.

Sorry to have wasted your time chaps :eek:
Excellent news - and no time wasted. Glad to have been of service :thumb:

Oh, and I know what you mean about wishing you'd known about DI Vessels 25 years ago. I reckon I could have saved myself a few days in aggregate over a similar period!
 

jotter22

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My hat is off to you Fudger...How many on here would have said " of course it is the right way around...However i got a new hose and now all is fine....:D

Tony.
 

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