The other day, in a lazy moment, I used water from the hot water wand on my Magister Stella to make a cup of tea, instead of using the teakettle. It was not good! We drink a fair bit of tea and do know good from bad. That got me wondering, so I did a search on H-B and found lots of references to using the hot water wand for making tea, americanos and such. Why was my tea 'off'? I believe the answer is simple. On an HX machine the hot water from the wand is not the same as water from the reservoir, due to the way HX machines are plumbed.

In an HX machine, the boiler water is not used to make coffee. The path from the reservoir to the cup is via a tube that passes through the boiler in complete isolation from the boiler water. But, the water from the hot water wand is boiler water. Of course, since all boiler water comes from the reservoir, one might think that the difference would be slight. It isn't.

Each time we use the steam wand, we remove pure water from the boiler. This water is in essence distilled water. In my case, about 30g of it every time I do two cups of double cappuccino. Since we are taking distilled water out, what is left in the boiler is somewhat harder water, because we are not taking out any solids, dissolved or otherwise. Over time, the hardness of the water in the boiler rises.

So, I conclude that the hot water wand on an HX machine is only good for is to preheat cups and for maintenance of the machine, not for making tea. By extension, if boiler water taints tea, it must not do much good adding it to coffee drinks either.

I suppose most of the members of this forum already know this. I did too...just never thought much about the effect in the cup.

It all depends how much you turn over your boiler water. I make a pour-over using boiler water every morning, and I also use boiler water for a variety of other applications. With frequent use and refills it stays nice and fresh.

The other day, in a lazy moment, I used water from the hot water wand on my Magister Stella to make a cup of tea . . .

I would have used water from the grouphead instead, as I do frequently.

I agree, unless you use your hot water tap on a regular basis, the water in there ends up not tasting so great.

We use it more often than not to warm up our son's thermos, or for whatever else reason we need piping hot water for other things aside from consuming it. Darn shame though, having that nice handy tap right there for tea!

I read somewhere, probably this site, that it is good practice to drain off 100 ml of water from the hot water tap on a regular basis to help reduce buildup in the boiler and keep the water tasting better. I do this about every other day before shutting the unit down. I know the boiler tenders at the industrial plants where I worked did a "blowdown" on a regular basis to purge chemical buildup but the water was tested thrice daily (food plant) in order to determine when they did this procedure. It certainly cannot hurt to purge the boiler when you remember to do so.

This is a great topic. I used my hot water wand this morning to fill up my 300ml Monarch kettle to brew a 10oz V60. It was so fast and convenient that may never use an electric kettle again for my morning ritual. The coffee tasted fine as far as I could tell... the water didn't seem tainted or whatever.

Also wouldn't the water from the Steam Boiler be way too hot for making tea? Or at least a factor I would think.

Not really, the temperature at which it exits is admittedly super hot (above 100 C), as the boiler pressure does this as a matter of basic physics (STP). However, once the super-heated water is at atmospheric pressure, it very quickly drops down to the 100-degree boiling point. Most teas are supposed to be made with boiling water, or water just off the boil. A few, however, are better somewhat cooler. We use our electric kettle for this (and for pour-over), as it has digital controls that give us the exact temperature we want.

Agreed, the issue we had is purely because we do use the hot water wand often. There would be no issue if we used it daily, or even a bit less frequently.

Thanks for the interest in my little topic/observation!

Actually, the water in the boiler is "anti-distilled".

If you remove steam from the boiler, you are removing the purest part of the water. The remaining liquid becomes more concentrated in mineral content if it is never purged and refilled with fresh occasionally.

I agree that whether your boiler water remains palatable depends on the turnover of the water and of whether you pretreat it. In my experience using a water softener and making frequent use of the hot water tap keeps the boiler water well-suited for tea-making. Apart from tea of americanos I use it regularly to rinse the filter basket as well.