Very soft water fools boiler fill sensor - better idea than adding a little salt?

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#1: Post by espressoheadyvr »

My nuova simonelli Oscar "fill water warning" light kicks in with my "soft" tap water; so i have to put in a little salt into the water tank to push up the mineral content...the service guy at NS actually suggested that.

The trick does work but i'm concerned about the possibly negative effects on the machine by having salt in the lines (we're talking 3 or 4 shakes of salt - barely 1/4 tsp).

Is there a less potentially destructive way to fool the oscar into thinking there is water in the machine; seems oscar "sees" water level thru a water sensor that measures mineral content - and if no mineral content - no water being seen.

And of course I happen to live in british columbia where are tap water is so "pure" it has virtually no mineral content.


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#2: Post by HB »

I've heard of reverse osmosis water being so low in mineral content that the fill sensor would not detect ground, but never tap water. Instead of salt, why not add a few ounces of your favorite bottled mineral water? Or use a calcite filter (look under mineral additive).
Dan Kehn


#3: Post by ntwkgestapo »

Calcium Carbonate (or Calcite, see for a definition of the "calcite" variant of Calcium Carbonate...) Chris Coffee offers a filter cart that will put a small amount of it into a "plumbed in" system (i.e. if you have high quality Reverse Osmosis water OR, in your case, extremely pure tap water)...

For a pour over I'd recommend finding a source of Calcite or Calcium Carbonate crystals and putting a very small amount in...
Probably VERY Small...
Steve C.
I'm having an out of coffee experience!
LMWDP # 164

espressoheadyvr (original poster)

#4: Post by espressoheadyvr (original poster) »

Thanks folks...


#5: Post by kwksilver »

Here is an idea where you have to finish the train of thought but I am sure it leads to the right solution.
We just went through the different kidney and gallstones one can develop in med school. And we learned that for each ion salt to precipitate out, there is a preferred pH range.

You cannot play with your pH, as you need to preserve taste.

You CAN however choose the charged ions you add to your water. If they do not negatively impact water taste they are game.

In medicine we simply go the other direction with urine pH to promote dissolution of the formed stones. I am sure you can apply this and add a small amount of ions that do not favor precipitation at the pH of your water.
Since you know the temperature and you know the pH, I am pretty sure an inorganic chemist can give us a very fast and dirty way to start with DI water and add the minimal ionic species we want to have taste right and precipitations minimal while preserving electrolytic properties.
(There is no way we don't have someone with at least Bachelor level chemistry here, this board is packed with knowledge)

plus ça change, plus c'est la même chose


#6: Post by DavidMLewis »

ntwkgestapo wrote:For a pour over I'd recommend finding a source of Calcite or Calcium Carbonate crystals and putting a very small amount in...
Probably VERY Small...
You don't have to worry about it, because a saturated solution of calcite in room-temperature water is just about ideal for use in an espresso machine, around 90 ppm on my (probably slightly low) meter. All you need to do is make sure you have an intake screen that will keep it out of the pump, and you can put calcite crystals, washed to get the fines off of them, right in the reservoir. If that makes you queasy, keep the water and crystals in a bottle and pour off of that, or as another poster suggested mix in some mineral water. You want around 100-150 ppm for a good balance between taste and frequency of descaling. If you want to know more, search for "Insanely Long Water FAQ" by our own Jim Schulman.



#7: Post by 12much »

scandinavian coffeemachines are always equiped with floaters instead of sensors. So that will be the utimate solution.

However not easy to realize, just for the idea.

suc6 with brewing, Boy

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#8: Post by Stuggi »

I'm not sure if you could use sodium carbonate (washing soda crystals) for this, but it should be possible, and it should also be internal friendly compared to salt (sodium chloride) since it doesn't contain chloride ions... I'll research this further.
Sebastian "Stuggi" Storholm
LMWDP #136