OK, so I broke down and now a KvdW Speedster Idromatic is on the way, very soon to be arriving. I've been feeding our Izzo Alex Duetto III with copper boilers that is plumbed in with a BWT Best Head Flex & Best Max Premium 'V' water filtration system (bypass set to 3) and cartridge.

Given that the Speedster has Stainless Steel boilers and with our water chemistry in Montreal, what would be the best suited BWT cartridge to purchase if other than the Best Max Premium, that would be adequate and what bypass setting would be best? Would the smallest size filter (S) be adequate since we now know that we can never exhaust a Medium 'V' size cartridge within even 2-years?

https://ville.montreal.qc.ca/pls/portal ... T_2012.PDF

https://portail-m4s.s3.montreal.ca/pdf ... _water.pdf

We would be in, "West Montreal'.

TNX

BaristaBoy E61 wrote:iven that the Speedster has Stainless Steel boilers and with our water chemistry in Montreal, what would be the best suited BWT cartridge to purchase if other than the Best Max Premium, that would be adequate and what bypass setting would be best?

By most standards I think it would be considered adequate. The issue here is that the Bestmax is a decarbonizing (WAC resin) filter, which is not a good choice when you have high chloride but do not have high alkalinity. Your Montreal reports indicate a chloride ion level in the mid 20 - 25 mg/L ballpark and an alkalinity in the 90 - 100 mg/L (as CaCO3) ballpark. Your chloride is just under the 30 mg/L level that they use as a max allowed level in the Kees Speedster manual. Your chloride and bicarbonate alkalinity numbers are also within what Pentair once recommended as being OK with the use of decarbonizing filters: /downloads/ ... pdated.pdf


At least one manufacturer (Synesso) is more cautious about chloride corrosion risk. They recommend that water have less than 15 mg/L chloride ion for use in their machines. If you wanted to be extra cautious about chloride corrosion risk you might consider a reverse osmosis with remineralization system. RO is the practical way of reducing chloride to very low levels.

Or perhaps consider a conventional softener like the BWT bestprotect. It would do nothing to reduce the chloride ion, but unlike the decarbonizer* it would keep the alkalinity level high and would not acidify the water, which would help alleviate the chloride corrosion risk.

If you stick with the Bestmax, you'll want to run it with a high bypass to keep the alkalinity up around 40 mg/L or higher. For your total hardness of 120 mg/L as CaCO3 ( 6.7 °dH) I think they recommend a setting of 3 (their highest).

BaristaBoy E61 wrote:Would the smallest size filter (S) be adequate since we now know that we can never exhaust a Medium 'V' size cartridge within even 2-years?

The V has 2.4 times the capacity of the S, so you may get around a year out of an S before it's used up, which would be economical. (You do want to replace them at 12 months even if not depleted.)




* Decarbonizing filters exchange a pair of H+ ions for each hardness ion (Ca++ or Mg++) that they remove from the water. The H+ ions are buffered by bicarbonate in the water and you end up with lower hardness, lower alkalinity, and a more acidic pH. All three of those factors work together to make the water less scale prone.

Thank-you very much Pat.

If I understand correctly, a small Best Max Premium (S) filter that is set at by-pass #3 & replaced annually will just barely suffice but is not optimal.

Will this result in Stainless Steel boiler wear or rust over time?

I remember reading somewhere in their literature, "not for copper or galvanized steel". That does not inspire confidence.

I will give some thought to replacing this system but with what, RO?

Thanks again Pat. Your sage advice is incalculable.

BaristaBoy E61 wrote:If I understand correctly, a small Best Max Premium (S) filter that is set at by-pass #3 & replaced annually will just barely suffice but is not optimal.

After checking the price difference between the S and the V, I think your best bet is to just stick with the V and replace it every year even tho the resin is only about half used at that point. That will cost you ~ $160 per year. If you were to use the S, and if it exhausted in, say, 11 months, your cost would be $130/11 months = $142 per year. Barely lower, and not worth the hassle of assuring that you replace it before the capacity is exhausted.

BaristaBoy E61 wrote:Will this result in Stainless Steel boiler wear or rust over time?
I remember reading somewhere in their literature, "not for copper or galvanized steel". That does not inspire confidence.

The chloride corrosion risk for stainless is pinhole corrosion. The Pentair doesn't discuss copper, but I think it's even more serious for copper because of the 'bronze disease' effect of chloride on copper corrosion.

I'm pretty sure you should be OK with your Montreal water's chloride and alkalinity numbers. But corrosion is a complex issue, and Synesso may be on to something with their very low chloride recommendation. So going to RO in this situation is a way of playing it extra safe with an expensive or vintage machine that you want to last for decades. The high end (1000$+) RO systems that they sell to coffee shops have more capacity than you need, but do have a precision blending valve capability that might be useful. A typical undersink RO (APEC, iSpring, Homemaster) with a calcite remin cartridge would give you soft (20 - 60 mg/L hardness and alkalinity) water with near zero chloride ion. It would be more expense and maintenance effort than your Bestmax system.

There is also the option of using a coffee cart approach to plumbing in a carboy system. That would allow you to make your own recipe water as well as put your coffee station in places where the plumbing can't easily reach: Espresso Cart - Goodbye Plumbed In.

Does the Best Max Premium 'V' at least fall anywhere near or within the 'SCA Core Zone' for water (page 3 Speedster Installation & User Manual)?

https://www.keesvanderwesten.com/asset ... manual.pdf

I haven't figured out yet the conversion from ppm to mg/L

If this was your situation, water & machine, what would you be installing?

Thanks Pat

BaristaBoy E61 wrote:Does the Best Max Premium 'V' at least fall anywhere near or within the 'SCA Core Zone' for water (page 3 Speedster Installation & User Manual)?

If starting with water like yours at around 100 mg/L hardness and 90 mg/l alkalinity, that filter at a bypass of 3 ought to get you into that zone. Here's a post with a graph that depicts and discusses that SCA core zone: Good references on water treatment for coffee/espresso.

BaristaBoy E61 wrote:I haven't figured out yet the conversion from ppm to mg/L

ppm and mg/L for our purposes are the same (because a liter of water weighs 1000 grams, or 1,000,000 milligrams, 1 milligram per liter works out to 1 part per million).

BaristaBoy E61 wrote:If this was your situation, water & machine, what would you be installing?

I'm risk averse about corrosion, so I would go with either RO and remin, or more likely rig up a carboy system. I find it easy and inexpensive to buy de-ionized at the grocery refill and make recipe water, and my plans for a renovation would put my coffee area in a place that can't be easily plumbed.

OK, Thanks Pat!