Espresso water with whole house water "conditioner"

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.
curiousone

#1: Post by curiousone »

Hello--

New user here. I have been lurking for a while -- you guys are GREAT, I have learned a lot. Here's a question that I think is right up your alley and I would really appreciate some input.

We have an APEC whole house system (coconut carbon filter then water conditioner) plus RO at the kitchen sink. To be clear, by water conditioner, we are talking about a system that purports to neutralize calcium and magnesium so that they form crystals that move through the water without clumping together to form scale. (From their website: This system uses an advanced ceramic media that effectively attracts and neutralizes hard water properties without the need for regeneration, backwashing, or electricity. When water comes into contact with the catalytic surface of the media, hard water agents calcium (CaCO3) and magnesium become attached to the ceramic granules and are instantly converted into a scale resistant crystalline form. These crystals are harmless, neutral, heat resistant, and completely stable and will not attach to any surfaces like your pipes and heaters to cause lime deposits. When the crystals reach a size in the range of nano-meters (one billionth the size of a meter) they detach and are carried away by the water flow. These nano-crystals are relatively insoluble, effectively isolating hardness up to 25 grains/gal. (420 mg/L) from the water chemistry.). This was sort of a leap of faith for us but we definitely did not want a salt-based system.

We originally got this thinking we would use RO water in the machine, which we now know is wrong. Eventually, we decided to use the RO water and add back minerals. I don't make solutions, I just use a gram scale to add .8 gr epsom salt and .15 gr baking soda per gallon of water. Usually results in about 115 TDS.

Now I am questioning if I can just use the water from the tap rather than the RO. That water goes through the carbon filter and the conditioner so, theoretically, it should be free of chlorine and other unwanted compounds that could affect taste and aroma and it should pass through the machine without causing scale or maybe with a reduced propensity to form scale. FYI, the water from the tap is showing TDS around 205, so within SCAA limits. I have not done further testing (hardness, alkalinity, pH) yet.

A few questions:
1. Conditioner system aside, how much of a risk is scale build up at around 200 TDS? Does the SCAA recommendation suggest I shouldn't worry about that to begin with?
2. Anyone have any experience with this type of water conditioner system? Does it work? At water with a TDS around 200, to what extent would it be successful in preventing or slowing the rate of scale formation? Would you trust putting conditioned water through your machine?
3. How can you examine the machine to see if you are building scale rather than just waiting for problems to start ? I can take the cover off but I have no idea where to look to see if it is building scale.

Thanks in advance!

Pressino

#2: Post by Pressino »

If you are talking about a cation exchange resin water softening filtration system, such a system exchanges sodium for calcium and magnesium cations and does not form calcium and magnesium "crystals" that circulate harmlessly (i.e. without forming scale) in your home plumbing and appliances. Replacing sulphate anions with say chloride in "permanently hard" salts like magnesium sulphate can make them "temporarily hard" but that would be of little practical benefit for your intended goal of reducing scale in espresso machines.

Can you supply a reference to the house water conditioner you are talking about?

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homeburrero
Team HB

#3: Post by homeburrero »

I'm pretty sure that the APEC water conditioner is not a cation exchange softener. It is a TAC or NAC (template assisted nucleation) conditioner that uses a ceramic coated polymer to create crystals that stay suspended and don't form scale. TAC has been demonstrated to work in water heaters, but I'm unsure if that translates to effective scale prevention in espresso boilers. I have noticed that one reputable company, Optipure, uses it in their ScaleX2 system for use in coffee brewers.

We had some discussion related to TAC systems here on HB a while back: Template Assisted Crystallization (TAC) Water conditioning

curiousone wrote:1. Conditioner system aside, how much of a risk is scale build up at around 200 TDS? Does the SCAA recommendation suggest I shouldn't worry about that to begin with?
200 ppm TDS could certainly be very scale prone if much of that were due to calcium and carbonate. To do a good guess you need to know the hardness and alklalinity of the water and do an LSI calculation per Jim Schulman's Insanely Long Water FAQ.

curiousone wrote:2. Anyone have any experience with this type of water conditioner system? Does it work? At water with a TDS around 200, to what extent would it be successful in preventing or slowing the rate of scale formation? Would you trust putting conditioned water through your machine?
Perhaps others can weigh in about that. Given that there are ion exchange treatments that have been around a long time that are straight forward and known to be effective, I think I'd be reluctant to rely on TAC. If I had calcium hardness and alkalinity numbers that indicated light if any scale potential, then I might give it a try.

curiousone wrote:3. How can you examine the machine to see if you are building scale rather than just waiting for problems to start ? I can take the cover off but I have no idea where to look to see if it is building scale.
That is the rub. With a conventional softener you can use simple drop titration kits to measure the hardness and the alkalinity of the untreated and treated water and do an LSI calculation to see about how much it might scale. But those measurements don't tell you much with TAC -- the hardness and the alkalinity of the CaCO3 crystals do show up in the measurements, so treated and untreated water looks about the same.

To keep an eye out for scale in the steam boiler you can look at the water conductivity probe, or remove a fitting like the anti-vac valve and peek in there or use a boroscope. To check for scale in an HX or DB E-61 you can easily remove the mushroom and look for scale there: Checking an E61 Espresso Machine for Scale
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

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homeburrero
Team HB

#4: Post by homeburrero »

I should add that if you are measuring your TAC treated water with a TDS conductivity meter, the mineral content (dissolved and suspended) in the water is likely higher than what your meter indicates. I've been told (and it makes sense chemically) that if you do GH (EDTA chelation) and KH (acid titration) tests, the numbers reflect the hardness and alkalinity of the suspended crystals as well as the dissolved mineral.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

Pressino

#5: Post by Pressino »

Here is the main non-commercial (and so far the only one I've found) study of the scale inhibiting effectiveness of TAC water softening technology:

https://www.waterboards.ca.gov/water_is ... teners.pdf

It was interesting to read and at least when TAC was used within the experimental protocols of the study it seems to have prevented scale build up compared to no treatment at all. Note that according to this study even "magnetic" water softeners seemed to have some benefit (about 50% reduction compared to no treatment). TAC was deemed to provide about 88% reduction (though cation exchange resins provided more...about 99% reduction).

Read the protocols closely. The study was geared toward seeing how effective "alternative" water softening treatments would be in reducing scale formation in domestic "hot water heaters" {pet peeve...they are just "water heaters"]. So the test temperatures were at 60 and 80 degrees Celsius, which is considerably lower than the temps in espresso steam boilers, especially those maintained at higher pressures.

I understand the hypothesis by which these devices are supposed to prevent scale build up...i.e. the ceramic/bead matrix is supposed to make the scale causing salts to aggregate into larger crystals that have less tendency to "stick" to metallic surfaces and thus just pass through the plumbing.

My concern which has not been answered so far as I can tell is how well do these devices prevent scale, compared to more proven methods like cationic resin exchangers, water distillation, and RO, in espresso machines with steam and brew boilers that operate at much higher temperatures and with smaller water volume capacities and more restricted water passage orifices than are found in domestic water heaters?

My opinion, from what I've read so far, is that TAC may reduce scale to some degree, but almost certainly will not do so nearly as well as the more proven traditional methods.