How to descale HX espresso machine

#1: Post by **dgw** » November 15th, 2008, 1:59 pm

Just found this forum this AM -after my ECM Giotto overpressured! Sounds like I need to do some descaling - something I have not done before. My machine is about three years old, but we moved to TX from OR about 18 months ago - a big change in water. I've got some citric acid around in my homebrew supplies, but any suggestions on exactly how to descale this machine? Do I need to do a separate boiler descale? Do I run the descaler through the wand, the brewhead &/or the hot water valve? Do I just depend on the pump to circulate the descaler through the machine? Should I try descaling through the reservoir first or take apart the lines & soak them? Any and all advice is appreciated. Thanks.

#2: Post by HB » November 15th, 2008, 4:14 pm

I don't know what you mean by "my espresso machine overpressured", but as far as descaling goes, see the FAQs and Favorites entries below:

November 15th, 2008, 5:03 pm

Thanks, Dan. My gauge pressure went over 1.5 bar and the heating element did not shut off, causing the overpressure valve to release. I assume the pressurestat malfunctioned, either electrically or from scale clogging the line from the boiler. This has happened a few times over the past year, but shutting it down to cool had solved the problem up until today. I did a quick descale similar to the method described in the link you posted and, so far, it has been stopping at 1.5 bar, but when I have the time, I'll dive into the E-61 to clean it up also (although that's obviously not causing the pressure problem).
David

http://users.rcn.com/erics/ · #4: Post by **erics** » November 15th, 2008, 10:37 pm

David -

Making the unlikely assumption that the pressure sensing line that connects to your pstat is clogged, a great contribution you could make is to take a pic of BOTH ends of the line which connects to your pstat and post same. If the line has any scale buildup, soaking it in white vinegar or a citric acid solution would fix that in about an hour or so.

In addition, 1.50 bar is WAY TOO HIGH for the typical hx machine. A more reasonable max pressure would be around 1.15 to 1.20 bar, maybe even lower depending upon your steaming requiements. The TYPICAL safety valve on these hx boilers is set to release at 1.50 bar.

#5: Post by **mb514** » November 16th, 2008, 9:11 am

dgw wrote:Just found this forum this AM -after my ECM Giotto overpressured! Sounds like I need to do some descaling - something I have not done before. My machine is about three years old, but we moved to TX from OR about 18 months ago - a big change in water. I've got some citric acid around in my homebrew supplies, but any suggestions on exactly how to descale this machine? Do I need to do a separate boiler descale? Do I run the descaler through the wand, the brewhead &/or the hot water valve? Do I just depend on the pump to circulate the descaler through the machine? Should I try descaling through the reservoir first or take apart the lines & soak them? Any and all advice is appreciated. Thanks.

Disassembling the machine and giving the affected parts an acid bath is certainly the prescribed approach, but requires a certain level of skill with the machine or taking it in for service. My approach when faced with frequent pressure issues recently was to fill the reservoir with the cleaning solution, drawing it in to the boiler with the pump, letting it sit for 30-60 minutes, and then rinsing thoroughly. This improved the performance of my machine dramatically, but may not work for all p-stat issues.

November 19th, 2008, 9:20 pm

Fully disassembling a machine for an acid bath will certainly do the trick but should only be needed for extreme conditions. I simply overfill my boiler and heat exchanger with solution drawn from a tank, let it heat and soak for an hour, then flush it out with more solution, let it soak for another hour, then flush 4 tanks of water through the system to purge the solution.

#7: Post by **Beezer** » November 19th, 2008, 10:37 pm

Descaling is a good idea, especially if you've never done it before. But you probably still need to replace your pressurestat if it's overpressurizing your boiler. Pressurestats tend to fail after a year or more of use, and then they need to be replaced. This is not usually related to scale buildup, but rather to the electrical contacts wearing out. Fortunately, it's a relatively cheap and easy fix.

#8: Post by **mb514** » November 20th, 2008, 1:22 pm

cannonfodder wrote:... I simply overfill my boiler and heat exchanger ...

Is there a simple process for overfilling the boiler on HX machines in general?

http://users.rcn.com/erics/ · #9: Post by **erics** » November 20th, 2008, 1:33 pm

See here:

Simplified HX Descale [PourOver]

#10: Post by **Randy G.** » November 20th, 2008, 2:27 pm

mb514 wrote:Is there a simple process for overfilling the boiler on HX machines in general?

Look at the instructions for the Vibiemme DS on the 1st-Line site. it details the process, step-by-step:
1 - Download the full manual:
http://www.1st-line.com/machines/comm_m ... _press.pdf
2 - Then update it with the amended instructions for descaling:
http://www.1st-line.com/cofffact/vibiemme_descaling.htm