Well, I did my first DI wash and it's all it's cracked up to be. I used the TDS meter that came with the OTG kit and it read ~160ppm from the tap and ~3at the other end after ~15 second flush (and no pre-filter). I realized that I was missing one of the connectors/adapters to properly plumb the pre-filter into the setup, so, I ran a couple tests:
Tap: ~160ppm
Brita: ~95ppm
Prefilter (FloPlus-10) ~150ppm
OTD DI: 2-3ppm (no pre-filter, only tested immediately after the initial flush)
I was pleasantly surprised to see what looked like minimal flow reduction between my 50ft garden hose vs the DI filter connected to the tap via a 5ft jumper hose. So, it looks like the pre-filter will be the limiting factor for flow rate, which I've accounted for with the
booster pump, which I'll place before the pre-filter
txmav wrote Re question as to whether I recharge my filter: I haven't done this. I don't have a two tank system, and I don't see much cost benefit in doing the recharging. If I were to spend the money, I would buy an inexpensive pre-filter to take down the ppm the water before it goes into the DI filter.
This article was largely over my head (at least for a passive-interest level of understanding DI) but it explains a lot about the process of how various filtering, including DI works for various systems. In particular, it reinforced the benefit of a pre-filter to remove chlorine from the tap (Under the section: Causes of Irreversible Resin Degradation) to maximize media life and minimize degradation for refreshes.
That said, no pre-filter will materially reduce TDS without adding overall/long term cost. RO/DI/IE are the only processes that remove TDS, other types filters remove non-dissolved solids or liquids.
As to the cost of recharging/refreshing, several sources have essentially agreed with the longevity of recharges:
1st Recharge: Expect ~80% of the original lifespan.
2nd Recharge: Expect ~65% to 70% of the original lifespan.
3rd Recharge: Expect ~50% of the original lifespan.
It looks like one can get enough for ~3 refreshes pretty cheaply ($30-40), extending the lift of the ~25lbs/~$200 of media by 2-3x.
$15-25 for Base to refresh Anion: Sodium Hydroxide (Lye, Caustic Soda)
$10-20 for Acid to refresh Cation: Muriatic Acid/Hydrochloric Acid
Seems like a worthy effort to me. Admittedly, I'm solidly middle class... I'm sure many, on this particular forum, have the funds to not even care to think about saving a couple hundred bucks a year. So, I suppose my point is, I can afford it, but the geek/tinkerer in me feels like it's a worthy, fun little annual project.
txmav wrote I do not rinse before using the foam cannon on my car. From the two videos (linked below) that I saw, it seems that more dirt is removed from the paint by applying the foam to a dry car.
Thanks for the suggestion, and you're right... Yesterday, I totally spaced out, and forgot about starting with the foam. There was so much dirt/dust on it that I instinctively started with a tap rinse, then foam. But, in the end, it came out awesome! I made a point not to dry the windows/rims, just to see the difference. Of course I forgot to take a 'before' pic, however, the attached pics show how it came out, after a quick towel dry to the body and air dry on the windows! (I also forgot to use my leaf blower)
Now I just need to set up all of the equipment on my garden utility cart/trailer, for easy storage/transport! I'm MUCH more excited to wash my cars now, rather than feeling like a chore.