BaristaMcBob wrote:If you're not using the hot water wand regularly, it's not possible for minerals to build up. Where would the minerals come from if you are not replenishing the water in the boiler? Running the hot water wand unnecessarily is exactly the wrong thing to do if you're worried about scale. A daily "flushing" is actually just adding a fresh supply of calcium to your boiler. <snip>

I believe it is more complicated than this. If one did not use the steam wand, then this would be true. However, when using the steam wand, one draws off a few grams of pure water with each use, leaving behind all of the other elements of the boiler water. This increases the concentration of the solids in the boiler. This is where the hot water flush comes in. However, the quote is correct in the event that one is adding water with a higher concentration of TDS than is already in the boiler. But, this is not the OP's case; he has soft water. Also, in most cases, regardless of the water source, that source would normally be more or less constant in TDS; thus steam wand use without purging would always increase the TDS in the boiler.

Oops , I didn't see that Pat had already addressed this on the next page. Moderator, pls feel free to delete my post.

Okay. I did not realize how complicated it actually is. Thanks for pointing this out. Thanks to Nunas as well.

I read the link provided above. It suggests that one could possibly use distilled water to slowly descale a boiler. Since distilled water is not very conductive, would that cause the water level probe (HX machine) to not function properly?

BaristaMcBob wrote: Since distilled water is not very conductive, would that cause the water level probe (HX machine) to not function properly?

Correct. Your auto-fill wouldn't be trust-worthy, even if it worked at all. You couldn't leave the machine alone and on for fear of over-filling and flooding the countertop.

The best approach seriously is to just use a proper water softener designed to supply an espresso machine with the kind of water that flows in your pipes. There's loads of reading to do on the subject, ie. city water has Chlorine or chloramines in it, so the addition of hydrogen from a hydrogen exchange softener is going to make your water acidic, well water in my neck of the woods is so heavy in limestome that it's different from the almost pure water in aquafers under New Mexico or Arizona, etc. Lotsa reading, I know almost nothing about it and I've had to study it for years. A sodium exchange softener is of course not the best choice for an espresso drinker on a reduced-sodium diet.

Best to give the machine the best water you can, preheat cups from the hot water wand to circulate boiler water, check the boiler fill probe or mushroom if you suspect scale in one of the circuits and don't be too concerned, good machines are pretty tough, you can descale them if you get to the point where you have to.

Thank you. Yeah - I have something similar already. There's one caveat, though. Most homes have a pressure tank attached to their water main, which helps regulate line pressure. So even if the shut-off device works, I still end up with 10 liters of water on the floor...enough to ruin the wooden planks.

Okay. My water is soft and I already use a Best Cup mineral filter. But I do use my steam a lot and never the hot water tap. Sounds like I should just use the hot tap more often and not worry about it.

BaristaMcBob wrote:My water is soft and I already use a Best Cup mineral filter. But I do use my steam a lot and never the hot water tap. Sounds like I should just use the hot tap more often and not worry about it.

I think that's the easiest way if you are using soft water that normally never requires descaling. It's probably best to settle into a routine use of the hot water tap. Opening the tap and triggering an autofill before each steaming session may be enough. You can occasionally let the hot tap's water cool and check it with a conductivity TDS meter to satisfy yourself that it's not getting too concentrated.

BaristaMcBob wrote:It suggests that one could possibly use distilled water to slowly descale a boiler. Since distilled water is not very conductive, would that cause the water level probe (HX machine) to not function properly?

Yes. People who use that method must take care to either add some bicarbonate to the distilled, or add enough tap water to allow the water sensors to work properly.