Sure thing Dan!
Issue #1 - Vacuum Breaker Valve (after about 2 months of use!)
Here are the maintenance instructions from Clive Coffee on rebuilding the vacuum breaker valve: https://support.clivecoffee.com/ecm-syn ... eplacement
Note that there is a link on that page to the rebuild kit that they offer which contains the brass poppet with the o-ring preinstalled and the teflon block. https://clivecoffee.com/products/vacuum-breaker-rebuild
These are the replacement high-temp silicone o-rings that I ordered from McMaster-Carr for the vacuum breaker valve: https://www.mcmaster.com/9396K12/
I just removed the o-ring from the brass poppet, cleaned it up with a brass wire brush and installed one of the new o-rings. I then took some crocus cloth (VERY fine cloth-backed sandpaper) and made sure the sealing surface inside the teflon block was nice and smooth. Reassembly was simply the reverse of disassembly. Note that I did not need to remove the entire valve from the boiler; I just unscrewed the top portion (with the barb fitting) from the bottom while leaving it installed in the boiler.
Issue #2 - leak from back of steam valve assembly. (after about 14 months of use)
Here is a copy of the ECM Synchronika parts diagram courtesy of Whole Latte Love: https://support.wholelattelove.com/hc/e ... iagram.pdf
When I had a leak which presented itself as a slight "dribble" from between the base of the steam valve and the body of the machine, I tracked it down to o-ring #12 on page 10 of 15 in the parts diagram:
This article from Clive Coffee shows how to remove the steam valve assembly and remove that back part (#4 in the diagram) using a 6mm allen wrench: https://support.clivecoffee.com/ecm-syn ... eplacement
Note that original assembly used some sort of thread sealant between part #4 and the valve body so it took a fair amount of force to get it broken free.
The original o-ring was round so I found what appeared to be a suitable size high-temp silicone o-ring on McMaster-Carr: https://www.mcmaster.com/1283N28/
. But I saw that they also had the same size in a square cross section and thinking that the square profile may provide a greater sealing surface, I ordered a package of those ones as well: https://www.mcmaster.com/1182N017/
I had used a similar ID / OD rubber o-ring with a larger cross-section from a bathroom faucet rebuild kit as a temporary fix until the new ones arrived. Once the new ones arrived, I opened up the machine again and installed one of the square profile o-rings in the valve and lubricated it up with some 111 grease and re-installed the steam valve. While inside, I also replaced the plastic "T" routing the OPV and vacuum breaker to the drip tray with a 5/16" brass one I got from Amazon. https://www.amazon.com/dp/B077BH1T7T
That was just a preventative measure since I know the plastic one will eventually break due to the heat.
It has only been a couple days since I installed the new o-ring in the steam valve, but so far it is working just fine. It has been about a year since I replaced the o-ring in the vacuum breaker valve and it is still holding up just fine.
As a side note, I have only run RPavlis water made with Potassium Bicarb since I got the machine. After about 14 months, no signs of scale anywhere I've seen! Typical usage is 2 mochas for the wife per day (2:1 double shot, 8 oz of steamed milk plus Monin chocolate sauce) along with 1 double shot for me on weekdays and usually 3-4 double shots on weekends or when I have the day off! Machine is on a smart timer coming on about 5am and turning off about 4pm each day.
Hope this helps someone in the future!
PS - edited to add that we do 2-3 water backflushes after the last drink of each day and I backflush with a tiny amount of Cafiza (maybe 1/8 teaspoon) about once a month which also includes dropping and cleaning the shower screen, group gasket, portafilter and baskets with cafiza as well.