Rancilio Silvia Standalone Water Sensor

Holder for WS2 multiprobe water sensor.  Measure Rancilio Silvia espresso machine water tank level and report the information to home assistant via a template sensor and the ESP home integration.

BOM

• WS2 water sensor and 3 probes
• 6 10mm counter sunk M2.5
• 4 16mm counter sunk M3
• 6 4mm heat insert M2.5
• 4 6mm heat insert M3 
• USB power supply and USB C cable
• Female power connector (NEMA 1-15R)
• 2 piggyback spades connector connection to internal power
• 2 female spades and some 14 gauge cable.

Installation

• Build power adapter: it connects to the internal Silvia power switch, to a 2-prong female plug to a small USB power brick and a USB type C cable
• Install power supply in the Silvia, tight the USB-C cable to the back of the machine. The piggybacks and spades are connected behind the power switch: the sensor will report data only when the machines is powered.
• Install heat inserts:
• Install the probes and base. Remember which probe goes where, used when writing the home assistant template sensor below.
• Install the holder on the side of the heat shield
• Reinstall the back cover, making sure the USB cable is not squeezed. Since the sensor is at the top of the unit, the WIFI signal can flow through the water tank cover.
• Use HomeAssistant to report water level, by adding a template sensor:

In the state section of the template options sub-window, the last value is used when the sensor is offline. When online, the probes returns an approximation of the water level:

{% if not is_state('binary_sensor.screek_water_sensor_ws2_X_online', 'on') %}
  {{ int(states('sensor.silvia_tank_level')) }}
{% elif is_state('binary_sensor.screek_water_sensor_ws2_X_water_level_3_exists', 'on') %}
  {{ 100 }}
{% elif is_state('binary_sensor.screek_water_sensor_ws2_X_water_level_2_exists', 'on') %}
  {{ 50 }} 
{% elif is_state('binary_sensor.screek_water_sensor_ws2_X_water_level_1_exists', 'on') %}
  {{ 10 }}
{% else %}
  {{ 0 }}
{% endif %}

• Note that the probes must touch the reservoir. It may have to be push towards the holder to report accurate information.