How to Descale a Mini Vivaldi

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Endo

How to Descale a Mini Vivaldi

Post by Endo »

After a little more than a year of use, it was time to try and descale my Mini Vivaldi. I use RO water so I didn't expect there was much need, but I thought it coudn't hurt. I planned on making it part of my yearly maintenance routine (preventative maintenance), so I wanted to work out a simple method I could easily repeat when necessary.

I can usually can tell when the machine needs to be descaled by the sound. You will hear the brew boiler start creeking and whining as scale accumulates. My Mini started making these noises (mostly from the brew boiler), so I figured it was time.

There are few online methods. I also talked to the manufacturer and retailers who have there own methods. Most seemed overly complicated for the kitchen or invloved tilting the heavy machine (if you do not have the new steam boiler with the draing plug).

What I came up with is a very simple and fast method that uses simple items found in the kichen at no extra cost (and involves no messy tilting or lifting).

Here's what you'll need:
Required descaling tools
Required descaling tools
IMG_1672 (480x320).jpg (50.41 KiB) Viewed 31599 times
1. A 6ft line of 3/8" OD (1/4" ID) vinyl tubing. (Available for about $5 at hardware store).
2. 2 packages of descaling powder, to make 2 litres of solution (I use Dezcal).
3. 2 Litre measuring cup
4. Funnel
5. 19mm socket
6. Teflon plumbing tape
7. Flashlight

Here are the steps:

1. UNPLUG THE MACHINE.

2. Remove the top cover and use the 19mm socket to remove the vacuum breaker and brass cup from the steam boiler.
Remove vacuum breaker
Remove vacuum breaker
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3. Look in hole with flashlight to see the heating element coils. This will give you very good idea how much scale has built up.
Checking for scale build-up
Checking for scale build-up
IMG_1664 (480x320).jpg (51.67 KiB) Viewed 31599 times
4. Insert the vinyl tube into the boiler hole and place the other end a few feet below the machine, emptying into the 2 litre measuring cup. You can now easily pump out all the wter using a syphon method.

If you have never done this before, it is simple: Just suck on the lower end of the tube and when the water starts coming out, remove your mouth and the water will continue to flow until all water has been syphoned out of the boiler.

Once the boiler has emptied, check your volume of boiler water. You'll need to know this number for the refills that are coming up next (mine was a little over 800ml if you forget to measure).

Recheck down the hole with the flashlight to make sure you got everything. (You may notice some scale dust forming on the bottom of the boiler).

This method is so fast, clean and easy, it almost makes the new drain plug unnecessary!
Syphoning out boiler water
Syphoning out boiler water
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5. Next, put a funnel in the boiler hole and fill it with 800ml of decaling soulution (or whatever volume you measured in the last step). This will ensure the boiler is not over or under filled when you switch it back on. (Underfilled might expose the heating element, overfilling can cause problems too).
Adding Descaling Solution
Adding Descaling Solution
IMG_1678 (480x320).jpg (45.09 KiB) Viewed 31599 times
6. Empty the plastic reservoir and fill it up also with the remaing descaling solution (about 1.2L should be left). *TIP: Remove your hot water tap screen (it seems to collect a lot of scale as well). Throw it in the reservoir with the descale solution so it will descale too.

(continued in next post)
Last edited by Endo on Sat May 15, 2010 8:46 pm, edited 1 time in total.
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

7. Use some descale solution to briefly soak the vacuum breaker and cup. (It collects a lot of scale since every time the steam boiler starts up, some water escapes and dries out in the cup, leaving deposits which can make the breaker leak). Temporarily reinstall and torque the vacuum breaker and cup in place.

8. Plug the machine back in, but do not turn it on.

Hold down the "STBY" and "HOT WATER" buttons to draw descaling solution from the resevoir and into the brew boiler and out the group head. Draw about 450ml to fill the boiler.
Drawing Solution into Brew Boiler
Drawing Solution into Brew Boiler
IMG_1679 (480x320).jpg (54.28 KiB) Viewed 31598 times
9. Turn on the machine and let it warm up. Draw descaling solution through all water exits by steaming, using hot water and doing a water backflush.

10. Turn off and unplug the machine and let it sit 30 minutes with the descaling solution.

11. Next, you need to flush out all descaling solution.

Simply repeat steps 4 and 5, but use FRESH water to rinse out the steam boiler. I rinsed and syphoned twice too make sure I got everything out.

12. Fill the steam boiler one last time with fresh water (800ml), and re-install the vacuum breaker. You will need to add teflon plumbers tape to the threads since this will be an air seal and it will leak air (hiss) if you do not use tape.

13. Fill the plastic reservoir back up with fresh water.

NOTE: The sulpheric acid in the descale solution may remove the plating from the poorly made water inlet. It's just cosmetic so don't worry too much. Just make sure you get all the plating bits out!
Poor plating
Poor plating
IMG_1681 (480x320).jpg (52.67 KiB) Viewed 31598 times
14. Pull water shots until all descale solution is gone. This took quite a few shots (over 1 litre or about 15 shots). After about 10 shots (no sooner), you can try tasting (and spitting out) the water shots to see if all the solution is gone. (It tastes horrible so you'll know when it's all gone....probably not too healthy either, so spit it out quick).

That's it. My brew boiler is now totally silent when heating up! (Must mean something got cleaned). It probably doesn't remove everything, and you'll likely still need to open up the boiler if you use very hard water or let the machine go for a while without descaling. Still, I figure this mehtod will buy me a few extra years before I need to open her up or buy a new sealed Mini steam boiler.

Have fun and let me know how it goes.

EDIT: I changed the procedure so the descale solution is in the machone for 30 minutes rather than overnight. I think this is less risky to seals and plated components like the reservoir inlet....although less effective at removing serious scale build-up.
Last edited by Endo on Wed Apr 13, 2011 10:49 pm, edited 3 times in total.
Dodger1

Re: How to Descale a Mini Vivaldi

Post by Dodger1 »

Very nice job Endo! 8)
Barabus

Re: How to Descale a Mini Vivaldi

Post by Barabus »

Thanks for the process! When you visually examined the steam boiler, could you see a difference from before to after? Also, on my new Mini the brew boiler is silent but he steam boiler is somewhat noisy. Typical for this machine? The only reason I asked is because you noted a change in the sound for your brew boiler, but did not note anything for the steam boiler.
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

Good question.

When I looked in the steam boiler, the heating coils looked clean, so I didn't see much difference afterward. When I drained the boiler I saw what looked like dust on the bottom of the boiler (the vinyl syphon tube left a little mark in the dust). It seems to me this is where the scale settles first ( I think it's the same case on the bottom of the cylinder in the brew boiler?) This might be a good reason for the drain plug (or a removable top on the boiler like the S1, since the syphon won't suck this up). In any case, it looked amazingly clean after 1.5 years use. But this is probably because I only turn on my steam boiler for about 20 minutes each day and I use RO water.

The steam boiler always made noise since day one. I think it's simply a boiling noise from the high powered heating element and fan and not the sound you get when scale builds up (which sounds like bacon frying when the heater is on). This is the sound I got from my brew boiler. I leave this boiler on 10 times more than my steam boiler (sometimes all day). So I suspect it had more scale (but I can't see inside to verify).

The descaling eliminated the bacon sound from the brew boiler completely, and now I can't even tell when the heater is on. So I assume the descaling worked well.

The brew boiler is MUCH more expensive than the $169 steam boiler on the Mini so I really want to keep it in good condition. Luckily, it opens up in the back, so I plan on opening it after 2 or 3 years use just to check. The descaling just stretches out this date a bit and hopefully reduces the amount of scale to remove by hand once I open her up. I just don't want to do this too often since I need to open up the whole machine (all panels) and get a new nut gasket from CC every time.
caf4brains

Re: How to Descale a Mini Vivaldi

Post by caf4brains »

Endo,

Nice job in clearly explaining the descale procedure - the pictures are a great help too! My Mini steam boiler has been banging on startup for awhile now, so I suppose it is time to bite the bullet!
Thanks!
oton

Re: How to Descale a Mini Vivaldi

Post by oton »

EXCELLENT :notworthy:

How about the brew boiler? What tool to use to open it?
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

oton wrote: How about the brew boiler? What tool to use to open it?
The descale solution will delay build-up in the brew boiler, but since it gets used about 5 times as much as the steam boiler (for me at least), I think it's a good idea to open it up at least once every 2 years.

I haven't opened mine yet, but since it's the same as the regular S1, several forum regulars have already posted photos.

viewtopic.php?f=57&t=872

There is a brass nut on the back that can be unthreaded. It is an unusual castled shape, so you'll need to use a rag on the lugs and a pipe wrench. Be careful not to force it too much since cast brass will crack easily.

I think there is a gasket or o-ring under the nut as well. You'll need to get a new one from your retailer.
oton

Re: How to Descale a Mini Vivaldi

Post by oton »

:-(

Image

Again... So there's not a method to descale the brew boiler without open it??

The brew boiler was opened by a technician (to repair a water leak). But no descale was done.

By the way, this is the tool to open the big nut:

Image
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

The method I described using the syphon and Dezcal solution descales both the brew and steam boilers.

The method you show of using a square nose hook wrench to unscrew the brass ring nut is even better, just a bit more work. Once open, you can then physically descale the heater element and the inside of the brew boiler barrel.
oton

Re: How to Descale a Mini Vivaldi

Post by oton »

Frankly, the Descale issue disturbs me. I want something easy, like put vinegar or other product in the water tank to clean the 2 boilers. It's not possible?

This is what ISOMAC recommends for their machines

http://i54.tinypic.com/k2ig7n.gif
symbology

Re: How to Descale a Mini Vivaldi

Post by symbology »

oton wrote:Frankly, the Descale issue disturbs me. I want something easy, like put vinegar or other product in the water tank to clean the 2 boilers. It's not possible?

This is what ISOMAC recommends for their machines

http://i54.tinypic.com/k2ig7n.gif
I see no reason why you cannot use this method to descale both boilers. As a matter of fact, when the time comes it it probably the way I will be doing mine. I may make use of the drain on the steam boiler, but running through the brew boiler should be pretty quick.

-Allen
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

If you stick descale solution directly in the reservoir only, you would never get a high enough citric acid concentration in the steam boiler to do any good since since it already contains 1L of water. And besides, you'd never get the sour taste out afterward unless you syphon it out (or use the new drain).

Some may say to empty the steam boiler first through the new drain. But if you did, you risk frying the uncovered heating element before the boiler fills (and risk destroying your entire sealed boiler unit). So I don't see any way around removing the vacuum on top so you can fill.

I still think the method I show is the best, and it really is super easy. Of course if you have the new drain plug, you can replace the syphon part by simply draining out the bottom and save a few steps. All you need then is the wrench and funnel.
caf4brains

Re: How to Descale a Mini Vivaldi

Post by caf4brains »

Endo,

I followed your descale procedure on my Mini this weekend. I had one minor addition that may apply to some Mini owners. I was unable to get the 19 mm socket on the boiler vent valve because it was partially blocked by a cross-beam. In your picture there is a cut-out that would allow access but on my earlier(?) model the beam lacks this feature. I was able to move the boiler away from the beam by loosing the nut that apparently attaches to a bolt that secures the boiler to the adjacent partition. With the top off and standing at the operator side of the machine the partition is just in front of the steam boiler. The The bolt also is used to attache a green (ground) wire, which is how you can recognize it.

I used vinegar full strength and this seemed to work well. The steam strength through the wand is much improved.

Thanks for a simple procedure to follow!
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

Time for my annual descale again (plus I'm getting a bit more noise from the boiler than before). This time I plan to leave the descale solution in for only 30 minutes rather than overnight. I may have gone a bit too long last time and perhaps that's why I lost all the plating on my reservoir inlet. Also, it's a little safer on any seals.

I modified the procedure to reflect this change.
JohnB

Re: How to Descale a Mini Vivaldi

Post by JohnB »

From my experience 30 minutes isn't going to accomplish much of anything. The problem with not opening the boilers is that you have no idea how much scale you actually removed. Back when I bothered with citric acid I removed the heating elements & soaked the coils in a strong hot solution reheated several times on the stove. Even after several hours the build up between the coils was still there. The deposits inside the brew boiler are even harder to remove as they seem to be hard mineral deposits that take hold at the seam. These required more then an overnight soak with white vinegar which I switched to after the citric acid solution had little effect.

Doing these quick descale flushes that I've seen written up on H-B & CG is about as useful as running Grindz through your grinder & thinking you've actually cleaned out all the old grinds & oils. You may feel better after doing it but it hasn't accomplished much else. If opening the boilers is too much work then only use soft water so you don't get the scale in the first place.
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

JohnB wrote:From my experience 30 minutes isn't going to accomplish much of anything.
I tend to agree with you. The method I give is "preventative maintenance" at best.

Still, it does tend to eliminate the heater "crackling" noise, so it must do a little something.

I plan on opening up the brew boiler as soon as I get a replacement gasket and a spanner. On the other hand, since the steam boiler is sealed, there is nothing I can do here (I'll just minimize its use by using it "on-demand" and replace it after 15 years or so).
JohnB

Re: How to Descale a Mini Vivaldi

Post by JohnB »

I was thinking you had one of the new stainless steam boilers. Do they have a removable cover like the S1 or did they just add the drain plug? As far as the 30 minute soak you will knock off the softer outer layer but if you don't get the rest of it you will be descaling more often then if you just let it soak for hours or overnight. The brew boiler is a different story as I mentioned before. You won't get the same heavy scale build up on the element like you would in the steam boiler. Instead you see a very hard greenish mineral deposit that attaches to the boiler itself & eats into it. Left unchecked it could do some damage. You will also find various types of debris that gets trapped in the forward pocket which you won't get out without opening the boiler. My guess is that descaling without removing the cover to manually clean out the boiler will just add to this. Look at Onton's pic from last July & remember that you are drinking the water that has been sitting in that boiler.
Endo

Re: How to Descale a Mini Vivaldi

Post by Endo »

I haven't heard of any boiler changes on the Mini. As far as I know, all they did was drill a hole in the bottom and weld in a drain plug (that rusts). It has always been a welded shut stainless unit (no way to manually descale).
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