Descaling using distilled water?

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.
Satchmo780
Posts: 84
Joined: 2 years ago

#1: Post by Satchmo780 »

So recently purchased a used Salvatore Compact Lever - everything works. I live in an area with hard water (Georgetown, On), and even with a whole home sodium softener, we find we need to descale kettles and things reasonably frequently.

Now I've been using water treated with the BWT penguin pitcher to minimize accumulated scale, but I have no idea what the people who owned the machine before me did, and I'm sure that there's likely some scale built up in the machine - even if it's working well now.

As far as I can tell descaling the machine properly would be a boiler-out kind of job which I don't really want to tackle just yet, and I came across this older thread - Boiler descaling spring lever espresso machine

which mentions
Also, since Robert Pavlis was mentioned, he recommended an option of using distilled water in a machine that had accumulated some scale but was still functioning well. The scale would dissolve into the distilled water.
What would be the downside of running on distilled for a while, and how would I be able to tell when it had done its job?
LMWDP #737

User avatar
homeburrero
Team HB
Posts: 4894
Joined: 13 years ago

#2: Post by homeburrero »

Satchmo780 wrote:What would be the downside of running on distilled for a while, and how would I be able to tell when it had done its job?
I'm pretty sure your machine has a boiler level sensor probe that requires some minerals to work, so pure distilled would not be a good idea.


The next best thing would be to use distilled that has a small amount of bicarbonate added. Add a tiny pinch of sodium bicarbonate or potassium bicarbonate, in the neighborhood of 0.05 to 0 0.1 gram per liter of distilled. It will tend to dissolve limescale, albeit more slowly than would pure distilled water, which is slightly acidic. But since it has that alkalinity you can safely use it as your routine water and you have less need to know when/if it has cleared out limescale in your machine.

There is a variety of methods and recipes for making scale-free, bicarbonate-only water. See Easiest way to make rpavlis water?
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

Marcelnl
Posts: 3837
Joined: 10 years ago

#3: Post by Marcelnl »

I wondered how much scale will dissolve in distilled water, do you have any idea/guess? Heat will help, yet using Bicarb will indeed slow things down, just wondering if the proces takes on paleontological periods or more humane...
LMWDP #483

jgood
Posts: 906
Joined: 6 years ago

#4: Post by jgood »

What was said about the water level sensor -- it will not function properly with distilled. Don't ask how I know this!

User avatar
homeburrero
Team HB
Posts: 4894
Joined: 13 years ago

#5: Post by homeburrero »

Marcelnl wrote:I wondered how much scale will dissolve in distilled water, do you have any idea/guess? Heat will help, yet using Bicarb will indeed slow things down, just wondering if the proces takes on paleontological periods or more humane...
Good question. I think it would be very slow, but maybe not paleontological. :wink: As a rough guess, we know that RO water very slowly trickling through a calcite filter might dissolve at a rate of 30 mg/L. That calcite is finely ground, not hard deposits, but if you use that as an upper guess, and assume you have 1 liter per day of throughput and 5 grams of limescale deposits, it still would take over 6 months to dissolve. Water with a little bicarbonate will have less carbonic acid and would be slower, heat would also make it slower (calcium carbonates become less soluble at high temp), and of course the small surface area of the limescale deposits would make it slower. I'm guessing that it might take a decade to remove a few grams of limescale.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

Marcelnl
Posts: 3837
Joined: 10 years ago

#6: Post by Marcelnl »

Thanks Pat, I was intuitively thinking along the same lines....it's feasible but in quantities that are not practically meaningful.
LMWDP #483

JRising
Team HB
Posts: 3731
Joined: 5 years ago

#7: Post by JRising »

Marcelnl wrote:I wondered how much scale will dissolve in distilled water, do you have any idea/guess? Heat will help, yet using Bicarb will indeed slow things down, just wondering if the proces takes on paleontological periods or more humane...
Take out your boiler level probe and have a look at it. It will give you an accurate indication of how much scale is built up on the surfaces inside the boiler. The scale on it might be thick enough that you can break off a chunk to measure and drop into a shotglass of distilled water. Measure it again in 6 months to get an idea of how quickly slightly acidic, distilled water is re-dissolving the minerals.

Marcelnl
Posts: 3837
Joined: 10 years ago

#8: Post by Marcelnl »

The Urania was made before boiler level probes were invented ;-)
It's scale free, and I'm using detilled water (adding bicarb acc, to Rpavlis) so it was only an thought exercise!
LMWDP #483

matkuf22
Posts: 8
Joined: 3 years ago

#9: Post by matkuf22 »

It is an interesting thought. Is there any downside to descaling with distilled but otherwise using filtered/remineralized water?

User avatar
homeburrero
Team HB
Posts: 4894
Joined: 13 years ago

#10: Post by homeburrero »

matkuf22 wrote:Is there any downside to descaling with distilled but otherwise using filtered/remineralized water?
No downside other than it being relatively ineffective (compared to an acidic descaling solution) at quickly dissolving scale. In special cases, like calcium sulfate deposits, it may be more comparable because descaling solutions are also relatively ineffective.

Using distilled to periodically flush a steam boiler in order to prevent problems due to concentration of minerals caused by steam wand use is a common and recommended practice: Espresso machine water tastes really bad
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

Post Reply