Bottled Water and Descalling Espresso Machine
So Ive just seen a drop kit suggested by Rob in another thread that I’ll be purchasing and I’ll try managing the water using this and ther zero whilst I await deluvery of the Skuma.
Thanks to everyone for their help - this is a new area to me but something I need to get my head around before I take delivery of a Minima
Could you post a link to the drop kit suggested?
Ross
Sure - was this one:
From this thread, which I would recommend reading is quite a useful read too:
https://coffeetime.freeflarum.com/d/118-water-calculator-scaling-potential-and-remineralisation
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The hardness in tap water comes from carbonate salts as the majority source. There may be some additional sources in there too but dropping alkalinity down by cutting with zero water is almost certainly going to reduce hardness down to the point scaling won’t occur. Hardness would have to be roughly double alkalinity for scaling at brew boiler temps (at 40mg/l alkalinity). There’s probably an exception out there I just don’t think I’ve seen it.
LMSC Testing would mean destruction testing. I wouldn’t do that on my own equipment, so I use the consensus recommendations of people much cleverer than me, that have stood the test of scrutiny & review for 20yrs. :-) I have read every coffee related water paper I could find.
I prefer to keep my testing to things that don’t have catastrophic failure modes :-)
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Rob1 Hardness would have to be roughly double alkalinity for scaling at brew boiler temps (at 40mg/l alkalinity).
Thanks Rob. Is this generally the case for water in general or if this is zero water specific — because my question was zero water related.
How does this (hardness roughly doubling alkalinity) play for the service boiler please ?
MWJB Testing would mean destruction testing.
Thanks Mark! Sorry, didn’t quite understand this statement. Could you clarify please? 😊
When I said testing - I assumed drawing water from the boiler, letting it return to the room temperature and using drip kit to measure hardness.
Sorry, perhaps, I should have clarified! Thx
LMSC Sorry, didn’t mean to be mysterious, to my mind testing which water is good, which corrodes to problematic level, and which scales to a problematic level means 3 machines equally fed with different water, one of which survives. My Dad has done the scale test on a Gaggia Classic & 260ppm hardness/190ppm alkalinity water, stripped it twice in 6yrs, now it’s a project machine in my spare room. :-)
I have tested water, boiled it, then retested and I don’t recall seeing a difference…even if there is, I’m not sure this is meaningful if we already know the relationship between hardness, alkalinity, pH, temp & LSI predictions (all based on incoming, ambient water).
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MWJB Nicely explained ! Thank you.
Wow! your dad is a legend! I am not surprised water, brewing and stat have become your natural qualities.
I would never feed the machine with water having such levels of hardness and alkalinity. The only testing I have been doing since getting my Evo is a drop kit test for hardness and alkalinity of the re-mineralised RO water, which I regularly draw from the service boiler to find evidences of scale forming.
LMSC Thanks Rob. Is this generally the case for water in general or if this is zero water specific — because my question was zero water related.
How does this (hardness roughly doubling alkalinity) play for the service boiler please ?
I’m not sure what you mean by that really. Zero water is basically pretty close to pure, similar to RO. If you’re asking how long the jugs remain effective for I don’t know, but if you’re diluting to 40mg/l alkalinity all the time you’ll get consistent results you’ll just need to use more water from the jug as the filter wears out (the filter might not gradually stop working).
At service boiler temps it drops, say around 125c above approx 50mg/l hardness: 40mg/l alkalinity will scale.
If you pull water from a service boiler to test it, if scale is forming your test will always show the water as non-scaling afterwards. You can use a test to see if the water has more minerals compared to what you’ve been putting in, but you can’t determine when it started scaling and how much scale has formed without knowing how much water you’ve lost when steaming.
When i had a marine tank i used to use hanna checkers for ph, alk, etc
Id bet they do a fresh water version to not cheap tho haha
Decent De1pro v1.45 - Niche Duo - Niche Zero - Decent is the best machine ever made -
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if you pull water from a service boiler to test it, if scale is forming your test will always show the water as non-scaling afterwards.
Not sure, this is clear.
Let’s say, I steam, switch the boiler off, the machine off and draw some water to test. The usual 20 ml each and standardise for 5 ml.
At room temperature, the kit shows 40.28 mg/l alkalinity and 11.2 mg/l of hardness.
This is where your excel is valuable. I put this in your excel, I know already the maximum hardness allowed in cell B24 is already higher than the value shown by the drop kit. I don’t have to adjust alkalinity and hardness in cells B16 and B17 to see how many mg/l of scale has already formed.
Rob1 how much scale has formed without knowing how much water you’ve lost when steaming.
Based on the above observation of the data, for the given steaming. I don’t need to know how much is lost in steaming, do I ?
I understand some water lost in steaming as it leaves the minerals as deposit. In my Evo, for example, I steam 350g of milk once a day. After steaming for about 35s, the pump has never kicked in, during the last 6 months, unless I open the hot water tap.
I remember Dave recently posting in another thread, the water lost in steaming is not significant, perhaps, 30 ml is lost in per steaming.
So, for scale to become an issue, we need to steam a few times a day, leave the water to sit in the boiler, not draw something out regularly and do not flush out the water and replace once in 5-6 weeks.
The bottom line therefore is not feeding the machine with the water, which will scale. Always draw a cup or more water out weekly and do a full flush once in 6-8 weeks — in machines like Evo, it will be a half flush. Of course, descale periodically, may be once in a year, depending on the frequency of use.
Cuprajake That’s costs a fortune! 😀
I am asking all this because, many might not feel comfortable to ask. Hopefully, posts / threads like these will be seen as an enrichment of knowledge, help folks understand the importance of feeding good water, take simple steps to minimise scaling; assuming these discussions are not seen as argumentative 😊
@LMSC , “ At room temperature, the kit shows 40.28 mg/l alkalinity and 11.2 mg/l of hardness. “
What kit are you using ?
I do find this water stuff very interesting, and confusing !
I find it majorly confusing and I though I was ok using 50/50 Volvic /Ashbeck, now I don’t know anymore.
Ian
I also used a 50/50 mix but since last week I’m using Ashbeck with 0.2 gm per 5l of sodium bicarbonate to raise the alkalinity to approx 40mg/l
LMSC I understand some water lost in steaming as it leaves the minerals as deposit. In my Evo, for example, I steam 350g of milk once a day. After steaming for about 35s, the pump has never kicked in, during the last 6 months, unless I open the hot water tap.
I would find that really strange (unless you open the hot water tap every day or two). Maybe the evo just has a long refill and a deeper probe tip. On the Minima when I steam for about 15 seconds I’ll get a refill either the next morning when the machine turns on via timer or when I use steam again and the boilers cool down. Almost always get a refill when the boilers cool down/when the machine comes on first thing if turned off when still warm after steaming a larger quantity e.g 40 seconds of steaming.
The amount lost is small but it adds up quickly, especially when you are putting water in with hardness and alkalinity. With the Minima I fill the service boiler with approx 1700ml distilled water. Over the course of 4-5 weeks steaming approx 1 big jug a day (40 seconds of steaming approx) the boiler will need to be drained because from that point you’ll start to see scale building up.
The point I was making about testing water from the steam boiler is alkalinity and hardness reduce as scale is formed until scale stops forming, so no matter what happens when you test the water you’ll conclude it won’t form scale. Of course, you’ll see it’s right on the edge/just a little over limit. In your case, you can track how close it is to forming scale as alkalinity and hardness both rise over time, but you can’t perform a random test and know when it started to scale if it gets beyond that point.
LMSC So, for scale to become an issue, we need to steam a few times a day, leave the water to sit in the boiler, not draw something out regularly and do not flush out the water and replace once in 5-6 weeks.
Even doing this scale probably won’t be an issue for quite some time. I used Volvic in the old Expobar for months without descaling and didn’t have any issues.
Reading this makes me want to cry. Checking water levels before I put it into the machine was enough but checking what comes out as well??? Lol