How Often Do You Flush Your Steam Boiler?

Beginner and pro baristas share tips and tricks for making espresso.
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boar_d_laze
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#1: Post by boar_d_laze »

As part of my prep everyday before using steam, I partially flush the boiler by running the water tap until there's not enough pressure to push any more out. That's in the neighborhood of 0.75L water, from a 2.5L boiler.

My thinking is that this keeps the water and steam in the boiler tasting "fresh." Also, that it's smart to move the water level in the boiler around a little to help control scale formation.

You?
Drop a nickel in the pot Joe. Takin' it slow. Waiter, waiter, percolator

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another_jim
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#2: Post by another_jim »

That works to keep the mineral level close to that of the incoming water. It's more effective if you can use distilled water. The amount it needs to be done depends on how much you steam and how hard your water is. For instance, if you have steamed enough to replace the entire water volume in the boiler, you will have doubled the incoming water's mineral level (the minerals in the original water, now steam, plus the minerals in the replacement water)
Jim Schulman

Al deHyde
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#3: Post by Al deHyde »

boar_d_laze wrote:That's in the neighborhood of 0.75L water, from a 2.5L boiler.
I follow almost the same procedure for the same reason. I also use the hot water tap to rinse the portafilter. Every few months I drain the boiler and do a refill - just seems like a good idea. I test my water regularly, and find that the TDS (ie, the conductivity) of the boiler water consistently stays only slightly higher than the input water. Steam has never imparted a bad taste to milk. Initially, I expected a steady rise in the conductivity of the boiler water over time (as Jim points out), but I have not observed this to happen with my setup.

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Charbucks
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#4: Post by Charbucks »

Does this apply to us SBDU people? I haven't heard of doing more than just blowing out condensation...
LMWDP #530

Intrepid510
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#5: Post by Intrepid510 »

Not too often, probably once a week I will take a good portion out for the same reasons you describe.

However, I have flrted with the idea of placing a liter bottle of distilled water in the tank for the boiler to pull from so I wouldn't have to worry about the scale.The idea tho of running dry and not knowing it since the auto-shut off feature would be effectively useless, has so far kept me from doing so.

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boar_d_laze (original poster)
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#6: Post by boar_d_laze (original poster) »

Charbucks wrote:Does this apply to us SBDU people? I haven't heard of doing more than just blowing out condensation...
Kinda-sorta-maybe. With a small boiler SBDU you use such a high percentage of boiler volume in everday brewing/steaming it's going to be significantly less important.

When I had my Pasquini Livia 90, I flushed less often -- like the VBM story. But I got a lot more finicky when I switched to the Cimbali. It's reassuring to know that Marty, another Casa guy, is doing what I do for similar reasons. Can I call you "bro?"

FWIW, I'm very interested in hearing from guys who have HX machines with large boilers -- like an NS Apia, or an Elektra Sixties, e.g. -- at home.

BDL
Drop a nickel in the pot Joe. Takin' it slow. Waiter, waiter, percolator

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slybarman
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#7: Post by slybarman »

1st line recommended drawing 4-8 oz or so off the boiler of the Cuadra at the start of each day. I remember about 1/2 the time.

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another_jim
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#8: Post by another_jim »

Charbucks wrote:Does this apply to us SBDU people? I haven't heard of doing more than just blowing out condensation...
No.

You are flushing the boiler every time you make a shot. You can descale occasionally by following the instructions and filling the tank with citric acid, lemon juice, vinegar etc. HX people can treat their HX circuit the same way, and double boiler people their brew boiler (albeit the brew boiler will be larger and require more rinsing after a descale)

The steam boiler has no continuous water flow through it, just water in and steam out. This is what creates the additional maintenance factors.
Jim Schulman

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cannonfodder
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#9: Post by cannonfodder »

boar_d_laze wrote: FWIW, I'm very interested in hearing from guys who have HX machines with large boilers -- like an NS Apia, or an Elektra Sixties, e.g. -- at home.

BDL
I do a boiler dump every when I do my weekly detergent cleaning and machine/bar cleanup (elektra sixties A3). I do not use the boiler water for anything other than rinsing out a used cup or if I am real impatient I will dump the boiler into a pan for boiling pasta since the water is already near boiling. My TDS meter says my tap water is around 140ppm, I only descale the machine once a year and that is just for preventative maintenance, I could easily go 2 years without an issue. I also run the machine 24/7 and pull 3 or 4 shots a day on it.
Dave Stephens

sashaman
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#10: Post by sashaman »

On an HX, if you rarely use the hot water tap in normal operation I really like Jim's suggestion about using distilled water. Once a week when I do a normal cleaning routine I flush a full reservoir worth of distilled water through the boiler (plus a little bit of tap water so the auto shut off still works), and I also use distilled water for the backflush routine to leave the HX full of distilled water before I turn the machine off for the night. My hope is that by doing this I won't ever have to descale the boiler, and even scale in the HX should be kept to a minimum since it's getting a ~12 hour soak in distilled water once a week.

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