I decided to pimp up my Rancilio Silvia by installing an Ito microprocessor, loaded with the Leva firmware.

If you’ve not heard of it Leva supports temperature sensors, pressure sensors, flow meters and Bluetooth LE scales to measure and control temperature, pressure, volume, flow rate and weight. This lets you do pressure profiling, dose by weight etc. You can also see a plot of the data on your phone or computer (like a Decent).

For my household, where I’m the only coffee drinker, a single boiler machine works perfectly. The delay to get steam is minimal, and it’s more energy efficient as I’m only heating one small boiler (300ml).

Details on the firmware can be found here: http://projectcaffe.bplaced.net/index.html

The equipment can be purchased here (note, due to Brexit you need to use a forwarding company such as MailboxDE to get it into the UK): https://www.softwareandcircuits.com/division/circuits/products/ito/index.html

I intend to document my build and experiences here in the hope that some people find it interesting. The intent is to give a flavour of what’s involved, not a step by step guide. The installation instructions that come with it are very thorough (found in the firmware download on the caffe site). Water and mains electricity can be a bad mix, so ensure you understand what you’re doing (or get help from someone who does) before attempting similar.

    The first step was to make the plumbing changes. This is done first so that you can pressure check everything to ensure there are no leaks. My machine currently has a PID installed (which will be replaced by this) and it’s got the gigar automatic switch off module (which will be removed).

    Machine in current setup with the back removed is below. The control box and solid state relay have been unscrewed to make space for the plumbing. These will be moved/removed as part of the project.

    Install the flow meter

    This goes before the pump and measures how much water is fed into the machine. This has several advantages:

    • If operating below OPV pressure it can be used to control dosing
    • It can be used to trigger maintenance and cleaning, such as when to descale, when you need to change your filter, when you should chemically back flush
    • It can be used for feed forward heating control. I.e. start heating the boiler before the temp drops because it knows cold water is coming into the boiler
    • It can stop the pump automatically if the tank is empty.

    Installation was pretty easy, it just involved pushing onto some tubing. The flow meter is the small white plastic thing in the bottom right.

    Install the pressure sensor

    This is required for pressure profiling. By tracking pressure in real-time, and controlling the power to the pump, the machine has full control over the pressure.

    The change involved removing the pipe from the pump to boiler, and replacing with a membrane regulator (the black thing attached to the pump, reduces noise and water hammer, plus makes the fitting easier) and teeing off some piping for the sensor.

    I also removed the insulation from around the boiler. This is advised to improve temperature control, as the PID can only heat increasing cooling reduces the time to correct any small overshoots.

    I then tested it with the machine open (being very careful not to touch any electrical parts, as once plugged in and on they have mains electricity in) and checked I didn’t have any leaks. Everything was dry, so I reassembled the machine.

    I don’t want to be without coffee and this is my only machine, so where possible I’m trying to minimise the time it’s out of commission.

    Next step is the wiring. I’ve got a busy weekend, so this probably won’t happen until Sunday night or one night next week.

    tompoland Thanks. Luckily the firmware is already done. I’m happy with the hardware and wiring, but computer programming is not in my current skill set.

      Great project, following with interest.

      I’ll be starting my Silvia V5 project in a few weeks and this thread may make me change my plans.

        Norvin The only really annoying thing with Leva is how long the parts take. I think it’s a one man operation. He opens orders for a couple of days once every 3 months. He then sources all the parts over the next few months and sends them out. I ordered my kit in October, and it only arrived this week. To be fair it got to the mail forwarder in December, but I was away for Christmas and didn’t want it left on the drive.

        There are similar projects done with raspberry pi or Arduino, but this seemed them most complete. It’s the pressure profiling that I’m most interested in playing around with.

          Great work, following with interest. How big a difference did the membrane regulator make to pump noise?

          Contact me

            dfk41 No problem, it’s not the cheapest upgrade.

            The all bells and whistles Ito kit was 257.55 EUR, forwarding to the UK was 23.44 EUR, and then import duty/tax was £60.33. There were a few other bits I needed which I ordered from Germany (this was also a trial run for the forwarding) which cost 30.20 EUR plus 13.45 EUR for forwarding. So in total at today’s exchange rate it was £331.55.

            So not cheap, but I enjoy these sorts of projects. The installation is part of the hobby. Electronics projects always add up fairly rapidly to be honest. Hopefully, by doing it myself it gives the machine a longer life too, as I can change/repair anything that goes wrong.

            A SBDU machine is perfect for my needs. I especially like that I don’t really have to worry about water, as I live in Oxfordshire, so the water is hard. I use a Britta filter, and descale every couple of months, but the Silvia is so simple that I can take everything apart if needed. Parts are reasonably priced, and even if I have some issues it’ll probably still be cheaper than the running costs of a solution such as an Osmio, or the electricity from distilling.

            DavecUK It made it a fair bit quieter, but also changed the pitch to more of a buzz. I wouldn’t bother for sound alone, but I’m not that bothered by the sound of a vibe pump. The only negative I’ve found so far though is that it’s had a big impact on the flow rate. It’s dropped it to ~200ml/min. I need to check this isn’t due to something I’ve done, but I’ve seen others report similar. I’m not sure it matters as that should be plenty for espresso use. It does mean it can take a few secs to fill any air gaps in the boiler, but the Ito shot timer can be set to start counting from a specific minimum pressure, to remove this variable from the counting.

                  Very interesting project. Well done mate. I am reading this with interest.

                  hornbyben It’s dropped it to ~200ml/min. I need to check this isn’t due to something I’ve done, but I’ve seen others report similar. I’m not sure it matters as that should be plenty for espresso use

                  Just had a thought, which may really be silly or stupid! What about directing it to a reservoir - internal or customised external ? You then have a normal supply from the tank to the boiler ? I know it’s an additional workflow. 😊

                      I love seeing this sort of thing and I have so much respect to you guys out there who have the nerve, balls, expertise to do it. To me it is like someone who enjoys flying, owns a Cessna and decides it’s not exciting enough and therefore, goes on-line and sources the parts that enable them in thier spare time to put a jet engine in it.

                      I’m not blessed in that way, confirmed as I’ve said in a previous post, just taking apart to clean and replace some like for like parts on my old Gaggia, resulted in me blowing it up three times when trying to put it back together, before getting it right.

                      Hold on a darn cotton pickin’ minute! Now I come to think about it, the closest I have come to pimping something up which did actually work, was wrapping some non-slip tape round the smooth Gaggia steam knob… well, you’ve got to start somewhere.

                      LMSC There already is an internal tank. The membrane regulator is really there to make the plumbing from the pump to the boiler easier, as it mates with a PTFE pipe that can be cut to length with scissors.

                      The original pipe is steel braided, so can’t be shortened. If it turns out to be a problem I’ll probably look to source a replacement pipe that is the length I need (slightly shorter than the original). I’ll probably not worry about this for now though, only if i find it a performance limitation.

                          hornbyben 200ml/min. I need to check this isn’t due to something I’ve done, but I’ve seen others report similar. I’m not sure it matters as that should be plenty for espresso use. It does mean it can take a few secs to fill any air gaps in the boiler, but the Ito shot timer can be set to start counting from a specific

                          I think that’s OK, they do drop flow rate a lot. For espresso you don’t need so much flow, it just adds a “longer” fill and infuse phase. I think it’s a great project to get more out of a machine and something very similar to what I suspect Kafmasino were doing. A Decent is beyond the reach of many, but replicating many of the software functions, as you are proving, is not.

                          Contact me

                              DavecUK Indeed, that’s certainly my hope. It also means you can spread your purchases as the hobby grows.

                              1. Get a cheap machine and learn whether you enjoy it.
                              2. Add a PID to avoid annoying temperature surfing. I did this pretty much straight away as I had one kicking around in a box in the loft that work were throwing out about. It’s a proper industrial process controller (Eurotherm). If I bought it new I think would have been nearly as much as the Silvia 😂.
                              3. Add some form of flow profiling to play with the more advanced side

                              I think it’s very similar to Kafmasino. There challenge was that they wanted to make it accessible to the masses as a final product. These sort of community projects are great, and usually deliver the performance, but they can be a bit rough around the edges, especially with user interface. That’s fine if you don’t mind, but from memory they were targeting £1k, which while reasonable if it delivered what was promised isn’t much buffer for the costs of actually running a business (e.g. to invest, hold inventory, pay bills etc). I’ll be at around £900 including the machine and that’s with all the software being developed for free and me putting in all the installation and setup labour.

                                Well hornyben (I’m sure I’ve seen you in some films…Ahem!)…Ooops! sorry misread that it’s Hornbyben different kind of trains…

                                So, I’ve been inspired by your thread and made something to tackle the thorny issue of popcorning on my ROK grinder. After mulling it over and in true Blue Peter fashion, I came up with this!…..

                                Obviously this is V.1 but it works perfectly.

                                Now where’s that screwdriver I wonder what lies under the hood of me Sage dual boiler I could improve upon ;)

                                  hornbyben There already is an internal tank. The membrane regulator is really there to make the plumbing from the pump to the boiler easier, as it mates with a PTFE pipe that can be cut to length with scissors.

                                  The original pipe is steel braided, so can’t be shortened. If it turns out to be a problem I’ll probably look to source a replacement pipe that is the length I need (slightly shorter than the original). I’ll probably not worry about this for now though, only if i find it a performance limitation.

                                  I’ve only looked at it for about 15 mins but thought that if I were doing it I wouldn’t have the membrane regulator, the pump is quiet enough for me as it is. I would put a ⅛″ BSP tee piece on the pump (see my Silvia V3 thread) and mount the pressure transducer on the spare connection (instead of the gauge). That way you can keep the braided hose. It’s only an initial thought, there may be reasons why it won’t work.

                                    Pompeyexile I like you’re creativity. That looks like a problem that’s crying out for a 3D printed solution. Will it work any better? Probably not, but it will look a lot more elegant 🤣.

                                    This is the slippery slope of being a tinker. Although I have to say, I’ve found my 3D printer a lot more useful than I perhaps expected. I’ve had one since 2014 and it’s amazing how often I find useful things to print. The latest was a unicorn biscuit cutter to make some biscuits for my daughters upcoming birthday.

                                      Remove the old PID
                                      I took off the previous PID and all the associated sensors.

                                      Here’s what it looked like once it was gone:

                                      Here’s the pile of stuff I removed:

                                      Remove the energy saving box
                                      This involves removing the energy saving device, power switch, led lights and no longer required wiring. The original switch was 5v to talk to the energy saving box, rather than 240v.

                                      You then fit a new LED that came with the kit, and a Silvia v4 power switch. Route the mains power to the new switch.

                                      For the old momentary switch I swapped the brew button faceplate. This means that I now have a momentary press brew switch. This means the Ito can always control the pump (useful for many of the features) and the brew button will tell the Ito to start a shot.

                                      Rewire
                                      I did all the 240v wiring. This involved the following:

                                      • Piggy back power (live and neutral) to power the Ito
                                      • Run wires from the 3 way valve and pump to the ito (so it can control these)
                                      • Fit a solid state relay, connect to wires that were connected to the brew thermostat
                                      • Solder an on board power supply to the ito (it needs 5v to run)
                                      • Stick the ito to the machine
                                      • Tidy up the wiring with cable ties (this not only makes it look better, but also prevents any wires resting against the brew boiler
                                      • I also attached the temp sensor to the boiler with conductive epoxy glue (this takes 24hr to fully set)

                                      Here’s what it looks like now:

                                      I called it a night at that. The next step is to connect all the 5v side, I.e. sensors and the brew switch. It does mean that I’m now on filter coffee until I’ve finished the upgrade.