Great. And I'll be happy to test the kit/instructions when you have everything put together . I guess what I'm most concerned about is disconnecting the water line at its undersink junction and getting a leakproof connection to the pump.

Great post that has made me want to descale my Rancilio S27. I have the citric acid and just want to clarify how to best approach the project.

My plan is to mix about a gallon (or more) of the citric acid solution in a bucket and unhook my water line and use a short piece of water line dropped into the bucket. My S27 will be able to pull the solution up.

Is there a preferred way to introduce the solution into the boiler and displace the fresh water? Or is it as simple as drawing hot water from the hot water spout and have the pump pull in the solution? I'm also thinking rather than overfill the boiler, I'll just push the probe all the way intt the boiler. This will fill the boiler more than normal and should get above the water line. Would it be better to overfill?

Thanks for setting me in the right direction.

Joe

Well, I Managed to descale yesterday and all went well. I grounded out the autofill sensor and flooded the boiler. I let it sit for 90 minutes or so and flushed it 4 times each time pumping water out of the steam wand. Got some junk out but overall not too bad. Strange thing the pressure stat, while it holds the pressure fine, doesn't click like it used to and makes a mild hissing noise. Kind of curious as to why. Machine runs great otherwise.

Joe

Is this a bit too much scale for my Rancilio Silvia?

Before. Pic 1


Before. Pic 2


After.


Not 100% perfect cleaning, but MUCH better than before! I'll more than likely run something through the machine to descale it, I just bought this machine yesterday and I wanted to get it mostly cleaned up/out and running... the shots taste great, the machine runs great, no complaints about the Silvia.

Link to my recent post with my descaling experience.
http://www.home-barista.com/knockbox/rancilio-silvia-descaling-pictures-t8279.html

One question please - In order to eliminate all the citric acid solution from the boiler, how many liters of water I can run one time, whitouth stop the pump, when flush the boiler? I have a Bezzera BZ10 with a vibration pump and I am afraid to not damage the pump.

The vibratory pumps typically have a relatively low duty cycle. At least one data sheet for an EP5 at 110 V that I have seen suggests no more than one minute on followed by at least one minute off, for water at 20C, which is a lot cooler than that found inside most machines. I'd be more conservative than that, perhaps only 30-45 seconds on and at least two minutes off, especially if you are repeating that. The 220V/50Hz versions seem a little more forgiving, but I'd still be conservative.



Personally, I would use a siphon to flush most of the descaling solution.

Scuse me for the dumb question, but what mean for you "siphon"? Can you post a image/link?

Thank you,