To achieve preinfusion capabilities your meCoffee needs to control the pump and the valve of your machine.
This functionality requires Active PID.
Locate the brew button of your Silvia, this is the upper left button.
Disconnect the white wire from the upper left terminal of the brew button. This wire carries the NEUTRAL signal to drive your pump.
Now connect the two white wires together so your meCoffee is able to drive your pump.
Fetch the orange female-to-male wire from the set. Connect the female side of this cable to terminal #7 of your meCoffee.
Disconnect the combined orange and black wires and separate the two. The orange wire carries the NEUTRAL signal to drive your valve. Now connect the two orange wires together so your meCoffee can control your valve.
Finally reconnect the black wire to the upper right terminal so your meCoffee is able tot detect the brew button state.
The upper left terminal of the brew button remains unconnected.
Remove the existing double black wire from your pump and place the meCoffee white wire in its place. The double black wire remains unconnected.
Fetch the red female-to-male+female wire from the second cable set.
Remove the existing red wire from the pump and connect the female side of the meCoffee red wire in its place. The Gaggia red wire remains unconnected. Combine the female+male side of the meCoffee red wire with the red wire already mounted at the power socket.
Fetch the orange female-to-female wire from the second cable set. Connect this cable to terminal #7 of your meCoffee.
Remove the blue wire from the valve and mount the orange cable in its place. The blue wire remains unconnected.
Now trace the wires on your pump : find the one which is connected to the microswitch beneath your water reservoir. Now disconnect the wire from the other other terminal at the pump so the only remaining connection to the pump is from the water reservoir microswitch.
Now connect the male+female side of the white meCoffee cable to the freed up terminal.
Go into meBarista#Settings#Hardware#Output3 and change it from Valve to Pump.
Notice : hot water dispensing might not work anymore, please contact support if this happens. We might have a workaround.
You can adjust the preinfusion parameters