Hi. I already skimmed through the water treatment FAQs, but I think I need some advice specific to my situation.

The reason for this post is that I was having problems with wet steam (slight sputtering) which I suspected was caused by too high a level in my boiler. Although the machine was only two months in service and the sputtering had been happening since day one, I pulled the level probe just to see what I would find. I did find a thin coating of white material which I was able to remove in about one minute after scrubbing with a Scotch Brite kitchen sponge and plain water (i.e., no vinegar, no soap). I believe this to be something other than scale (as i will explain in the paragraphs below), but the vendor who sold me the machine is saying that they can't think of anything it can be other than scale. I don't agree, but to be safe I want to make sure my water treatment is sufficient.

I am located in Houston, which the city water quality report says the average total hardness is something like 120 or 130 ppm. The water report doesn't specifically state CaCO3 content or alkalinity, but I think it is telling that I have no issues with scale buildup in my wife's electric kettle which gets daily use and has been in service for over two years. I know that scale deposition rates are temperature dependent and that steam boilers run at higher temperature than electric kettles, but the kettle has zero scale buildup. There is only some mineral powder that brushes away easily with a dry paper towel, but the metal underneath is still shiny. Could it be that the minerals are depositing as scale in the steam boiler but as powder in the kettle?

Also, I have used a BWT in-tank softener since the day I got the machine. I follow good practices for refilling the tank the day before next use to allow time for the softener to do it's job.

The vendor's tech support recommended that I test my ppm levels after filtering and ideally calcium levels. I'm having trouble accepting that advice considering that the water softener should be exchanging ions to keep the ppm roughly the same, and measuring calcium levels requires sending the water to a lab for analysis. I haven't seen this kind of advice before, so it seems like overkill to me.

Unfortunately I don't have the option of direct plumbing to allow use of an in-line softener. So if BWT in-tank softener isn't going to cut it for Houston water, I'm not sure what my next option should be. I bought some Third Wave Water for Espresso, but I don't think that will be much lower calcium content than Houston water treated with the BWT in-tank softener.

So, if you're still reading at this point, I am seeking advice on the following.

1. Any thoughts on whether the white material could be something other than scale? Perhaps something related to manufacturing?

2. Assuming that the white material is indeed calcium scale, does this mean that a BWT in-tank softener is insufficient for Houston water? I.e., that I get sufficient scale buildup to affect my level probe in very short time frame?

3. Should I look for a better water option, or just accept that I need to descale on some frequency. BTW, my machine is an ECM Synchronika.


Here are some photos of the level probe before and after cleaning.

Mike-R wrote:1. Any thoughts on whether the white material could be something other than scale? Perhaps something related to manufacturing?

My guess is limescale (CaCO3) or possibly gypsum (CaSO4). Your steam boiler is hotter than your kettle. But also, the water in there can become concentrated - - If you use the steam wand frequently and don't drain or purge the boiler it can become very concentrated, increasing scaling.

Mike-R wrote:2. Assuming that the white material is indeed calcium scale, does this mean that a BWT in-tank softener is insufficient for Houston water? I.e., that I get sufficient scale buildup to affect my level probe in very short time frame?

Besides the concentration issue mentioned above, there's also a possiblility that you exceeded the softening capacity of your in-tank filter. With your water hardness of ~ 125 ppm (as CaCO3) or 7 °d, the BestSave S may be exhausted by about 70 liters of tank fillings.

Mike-R wrote:3. Should I look for a better water option, or just accept that I need to descale on some frequency. BTW, my machine is an ECM Synchronika.

If you don't cure the problem with a periodic drain of your steam boiler, you might look into a more predictable softener. Your Houston water is only moderately hard, but will probably drop scale depending on the alkalinity number. You could look into a more predictable softening system. If it were me, and on Houston main water's borderline high chloride numbers, I would use a conventional softener rather than a decarbonizing (WAC) resin softener. The Homeland HCWS, the 3M/Cuno ESP124, and the BWT Bestprotect, are examples of conventional (SAC resin) cartridge systems, or you can use 10" generic filter systems like this one at CCS. These would reduce your calcium and magnesium to very low levels without reducing alkalinity or pH. (When you have chloride corrosion risk, you don't want low alkalinity nor acidic water.)

Thanks for the detailed reply.

I have been purging about 1 cup of water about every third day. I will up the frequency to daily.

Thanks for the list of in-line softeners. I understand this is best long term solution when I eventually plumb the machine in, but I won't have the opportunity to do that until mid next year. In the interim, do you think I would be better off to stay with the BWT Bestsave M (but with more frequent replacement) or switch to Third Wave Water?

Mike-R wrote:I have been purging about 1 cup of water about every third day. I will up the frequency to daily.

I think that should be sufficient. Daily purging via the hot water tap works best when you know you have non-scaling water. In cases where you have harder water that requires a periodic descale, your best option is probably to periodically:
1) turn the machine off.
2) empty a lot of water out of the hot water tap.
3) refill the reservoir with mostly pure water (distilled, RO, de-ionized).
4) turn the machine on and let the boiler refill.
5) empty and clean reservoir, and go back to using your regular brewing water.

Mike-R wrote:Thanks for the list of in-line softeners. I understand this is best long term solution when I eventually plumb the machine in, but I won't have the opportunity to do that until mid next year. In the interim, do you think I would be better off to stay with the BWT Bestsave M (but with more frequent replacement) or switch to Third Wave Water?

The guaranteed scale free option here would be to start using pure water spiked with a little bicarbonate (R Pavlis water). See Easiest way to make rpavlis water? . That would eliminate all risk of scale and would also avoid chloride corrosion risk.

Another short term option to consider in this case would be to switch from the BestSave to using the Bilt/Oscar/Rocket in-tank pouch filter. It's probably no more effective than the BestSave at reducing limescale risk, but since it uses a conventional resin it would not reduce the alkalinity nor acidify the water, making it a better choice in the face of that borderline high chloride. These pouch filters contain no activated charcoal, so you need to use charcoal or carbon block filtered tap water.

Thanks so much. This is incredibly helpful.

My next steps will be to mostly drain the steam boiler and refill with distilled, then start using the Third Wave Water temporarily (because I have it and because the BWT softener is surely spent by now) until I can get some potassium bicarbonate to start making R Pavlis water. Hopefully I'll like the taste of the R Pavlis water well enough until I can eventually get a plumbed in-line filter/softener solution. If not, I can survive on milk drinks until then.

I assume that it is better to leave the minor scale in my machine than to descale it. At this point, it surely isn't going to affect the performance of my heating element or other components, and my understanding is that descaling is hard on the seals. If you think otherwise, please let me know.