I own an Elektra Microcasa Semiautomatica which is a heat exchanger machine. After a major repair and servicing of the machine I started using distilled water for the boiler in an effort to avoid any future scale problems.

In an email response from a major reputable online espresso machine retailer, I was told this: "Stop using distilled water as it is corrosive on brass boilers and will open another flood of problems."

Has anyone ever heard of this before? Does the downside of using distilled water outweigh the benefits?

Rick

Distilled water absorbs CO2 and does becomes mildly acidic. But there is no reputable data that it's acidic enough to damage brass or other espresso machine parts in the water paths. The tap water in the Pacific NW has very low mineral content; it is pretty close to distilled. And it is a blessing rather than a curse on pipes. Espresso machines in that area tend to last forever.

Jim,

Just wanted to give a public thanks for your H2O tome, "Jim Schulman's Insanely Long Water FAQ."
While the art major in me found he was able to understand and absorb about 30% of it (and flattering myself even at that), the espresso drinker in me who is concerned with extending the life of my soon-to-arrive, plumbed-in machine thanks you. It helped me decide on the best way to spend the least amount of money and get a system that will (hopefully) work well for me.

And a chapter or lesson will be appearing on my website the end of the month... I hope...

another_jim wrote:Distilled water absorbs CO2 and does becomes mildly acidic. But there is no reputable data that it's acidic enough to damage brass or other espresso machine parts in the water paths. The tap water in the Pacific NW has very low mineral content; it is pretty close to distilled. And it is a blessing rather than a curse on pipes. Espresso machines in that area tend to last forever.

Thanks Jim! If anyone knows water for espresso, it's you. I'll go back to using distilled water.

Rick

From a purely physiological perspective, I have read that distilled water can draw essential minerals from your blood, effectively diluting your body's mineral content. How unhealthy this is I'm not sure. With heavily mineralized water, some Doctors have theorized that it helps to reduce heart disease, because of the high content of magnesium. Some epidemiological studies have shown such an association.

Of course coffee contains it's own fair share of minerals, so it might be that what you lose on the swings, you gain on the roundabouts.

Ian_G wrote:From a purely physiological perspective, I have read that distilled water can draw essential minerals from your blood, effectively diluting your body's mineral content.

Keep in mind that the OP's Elektra Semiautomatica is a heat exchanger espresso machine, and one that doesn't have a water tap to boot. So its steam boiler provides the heat source for flash-heating the water from the reservoir to brew temperature and for steaming milk, but the boiler water is never consumed directly. I use distilled water in my Semiautomatica steam boiler; I don't drink that many cappuccinos, so one gallon lasts more than a year.