The S1 Cafe - Helping Your Espresso Dreams Become Reality

I use my steam boiler only for steam. I saw a suggestion for the GS/3 that one should pull water from the steam boiler periodically to, in effect replace the water. I wonder if anyone does that on their mini?

I think it is not a bad idea.

As I understand it, the water which is converted to steam exits the boiler through the wand, but the minerals stay behind in the water, and cause it to become mineral rich.

Every 3 months or so, I usually remove the vacuum breaker and syphon out the water so that I can look inside with a flashlight and inspect for scale. I use this opportunity to refresh the water to prevent mineral concentration. This is even easier to do on the new Mini since it now has a boiler drain.

After steaming is done, I draw about 2-3 oz, wait til it refills, draw another 2-3 oz, wait ti it refills, then power off the machine.
I use that water to brush the group screen/gasket further.

Using Endo's guide to check/clean the steam boiler, after 9 months, did not see any scaling.

expy98 wrote:After steaming is done, I draw about 2-3 oz, wait til it refills, draw another 2-3 oz, wait ti it refills, then power off the machine.
I use that water to brush the group screen/gasket further.

That's not a bad idea either. If you let the hot water tap run continuously, it will stop automatically after 250ml is reached, so you'd be replacing 1/4 of the mineral rich water with more balanced water. If you do this once a month, it's probably just as good as completely draining the boiler every 3 months or so.

I think I'll switch to this approach from now on, and delay the draining to only once every 6 months. I still think draining every 6 months (max 1 year) is still a good practice, if only for inspection purposes.

Interesting information, and another reason for me to enjoy an Americano once in a while. :)

Endo wrote:If you let the hot water tap run continuously, it will stop automatically after 250ml is reached, [...]

Endo, I assume this applies to the Mini. On the plumbed-in S1, I can take at least 1L at a time. It does have an automatic shut-off (time based), but it must be higher than 1L...

Only the Mini has the hot water limiter. Since the heater is the same size as the maxi, but the boiler is smaller, there is a risk the heater gets exposed to air and damaged if you draw too much water, so they added the limiter so the hot water comes out in about 250ml / 1 minute intervals.

Endo wrote:Only the Mini has the hot water limiter. Since the heater is the same size as the maxi, but the boiler is smaller, there is a risk the heater gets exposed to air and damaged if you draw too much water, so they added the limiter so the hot water comes out in about 250ml / 1 minute intervals.

The maxi also has a limiter (at least on mine). I've just timed it: it shuts off automatically after 32 sec. (tried three times in a row).

MIne has one as well.

Louis wrote: The maxi also has a limiter (at least on mine). I've just timed it: it shuts off automatically after 32 sec. (tried three times in a row).

Good to know. How much hot water is that?

I wonder if this is a relatively recent design change. I had both one of the original V1s and one of the original VIIs. I don't recall the hot water stopping on either of those machines until the pressure just dropped too low and/or the boiler got too cold to push out any more water.

Makes sense the cutoff would be on the Maxi too. Water comes out faster than it refills, so eventually, the Maxi heater would get exposed too (assuming it still has enough pressure). The Mini get cutoff after 250ml (or about 15 seconds, IIRC), so I guess they just doubled that time on Maxi for about 500ml, or roughly 30 seconds, since the boiler is roughy twice the size.

Endo wrote:

Louis wrote: The maxi also has a limiter (at least on mine). I've just timed it: it shuts off automatically after 32 sec. (tried three times in a row).

Good to know. How much hot water is that?

I'd have to check to be sure. It is at the very least 1L, as this is the largest amount I've ever pulled out (with a 4-cup measuring cup).