An EBS interface sensor board is installed adjacent to the fan coil unit in each apartment unit. A pair of sensor wires are attached to the zone valve wiring or the fan motor to capture run time of either device. A temperature sensor can be installed to capture the temperature of the incoming water. Degree/time data is then transmitted via the on board transmitter, repeated to the Central Unit and received and stored for billing use. Degree data is combined with BTU specifications for the unit and relative gas consumption is determined for the unit in CCF (100 Cu Ft).

When chiller operates, electricity consumed to run chiller is allocated based on run time and inlet water temperature (if included) figures to arrive at a relative figure for electricity used to cool apartment unit.