Draining your boiler periodically

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redbone
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#1: Post by redbone »

Wondering how many folks drain their machine boiler periodically.

I'm cognisant that stagnant water can pick impurities and drain my machine every week or after not using a particular machine within a week.

I understand that it's much easier to do with a light lever machine vs a heavier pump or pro-sumer lever.

Do some machines have easy access drain plugs for this purpose ?
Between order and chaos there is espresso.
Semper discens.


Rob
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RockyIII
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#2: Post by RockyIII »

A few espresso machines have boiler drains, but it is difficult to drain the boilers on most machines, especially with the safeties that are designed to prevent them from running low on water. My current machine has an open boiler which is drained after each use by simply by lifting the lever, but I never completely drained any of my previous HX or spring lever machines. I just ran water out of the hot water tap as fresh water was pumped into the boiler, and after about three volume changes figured that was good enough. I only did that about every six months after performing a prophylactic descaling. During daily operation, I drained about 450ml just to help keep the water fresh.

Rocky

Nunas
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#3: Post by Nunas »

I guess it depends on the machine and how it is used. A single boiler machine is constantly being flushed; so there should be no need to drain it. A DB brew boiler would not need to be drained, but the steam boiler probably should be, as you're removing pure water (steam), leaving behind minerals. An HX would be more or less the same concerning the minerals, but since it is not boiler water that goes into the shot taste should not be a factor. Of course, if you often use the hot water from the boiler for drinks, rather than simply for heating mugs and such, I suspect an HX would not need to be drained, as it is constantly being flushed. I never use the boiler water for tea (tried it once and did not like it). And, I never use the boiler water in coffee drinks. So, I periodically draw water from the hot water wand to supplement that which I draw for heating cups. I believe that should keep the mineral content down, given that I start with only about 25 ppm TDS (yes, yes, I know...some of you like a higher mineral content :) ). My Magister has a drain...I've never used it.

Sideshow
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#4: Post by Sideshow »

Don't do it. Don't plan to.

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mania
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#5: Post by mania »

My Profitec Pro 300 DB manual said to drain Steam Boiler every 2-3 weeks (although it did not say how) :)

So I do drain it (every couple weeks or so )
What I do is after switching off I just open the hot water tap & it drains on its own while hot.
It is only .75 liter so seems I get all or most of it out

Then in morning when switched on pump refills it while cold

DeGaulle
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#6: Post by DeGaulle »

I use the HW wand for tea daily, while I use ion Exchange softeners as well. The water comes out crystal clear without flakes each time. As I have seen on my kettle, using Brita-filtered water reverses at least the initial scaling because it is said to slightly lower the pH of the water. So every 3-4 months before installing the new softener cartridge, for a few weeks I use water from a Brita jug that I otherwise keep for cold water consumption. I have never drained the boiler.
Bert

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another_jim
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#7: Post by another_jim »

There's several issues:

-- Scale: If you have a steam boiler and never or rarely use the water from it; scale will build up and the boiler needs to be flushed to control the build up.
-- Metal Leaching: If you have copper/brass boilers and use RO or low mineral water, the copper will leach over time. This is no problem if you are using the machine daily, since the water turns over; but the boiler should be drained if not in use. Steel boilers, as far as I know, do not leach.
-- Taste: Using hot water from your steam boiler very occasionally, rather than out of habit, may get you distinctly brackish and metallic tasting water. The easiest way to check is to tap a cup, let it cool, and taste it side by side with your input water.
Jim Schulman

Grant
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#8: Post by Grant »

I only specifically drain the boiler in my A3 when I descale a couple time a year to I can refill with an acid solution. I don't actually drain, as I siphon it as it's so easy to do.

I tip the machine to slant the boiler to one side, remove the vacuum breaker valve, insert some silicon tube, and then siphon out all the liquid. I then use the threads in the same hole to "screw in" a plastic funnel (it works great and seals water-tight) and fill the boiler with weak acid solution right above the boiler height (easy, because of the funnel sticking out the top). I then siphon out all the acid solution, refill with clean water and couple times, and then start it all up again.

I "aggressively" use my hot water wand to try keep the boiler water as fresh as possible though day-2-day.
Grant

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RapidCoffee
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#9: Post by RapidCoffee »

My Spaz S1 has a large (2.5l) steam boiler and a small (0.45l) brew boiler. I am not concerned about the brew boiler; espresso shots and grouphead flushes ensure that the water gets replaced regularly.

The steam boiler is another matter. I never draw hot water from the steam boiler for drinking purposes. There are many good ways to generate hot water for tea, americanos, etc. in the kitchen, but an espresso steam boiler is not one of them. I do, however, use the steam boiler regularly for steaming. So... to drain or not to drain, that is the question.

Steam is essentially distilled water. If you do not drain, and then the concentration of dissolved minerals in the steam boiler will increase over time, leading to more scale buildup. If you do drain, then you introduce a boilerful of fresh water, complete with a fresh batch of dissolved minerals, leading to more scale buildup. Classic case of damned if you do, damned if you don't.

Analysis is not simple, and depends on several factors. A couple of scenarios:
Do not drain. After some unspecified period of time, steaming reduces boiler level by, say, 25%. Some of the minerals leave the water as scale deposits. New incoming water adds 25% more minerals. Presumably the overall mineral concentration increases (by some unspecified amount), and scale deposits continue.
Drain and refill. The drained water has already generated scale deposits, so the mineral concentration is reduced. The refill water has the original (higher) mineral concentration. More minerals in the boiler generate more scale deposits.
Which scenario is worse? I can't tell, so I've gone the path of least resistance. I drain and flush once a year or so, when I run descaling solution through the boilers.

YMMV, because every machine is different.
John