Building device with near field communication circuit

A sensor device comprising:

• a flow sensor configured to sense a change in a characteristic of a flow of fluid;
• a processing circuit comprising a processor and memory, wherein the processing circuit is configured to utilize signals provided by the flow sensor according to a control program stored in the memory;
• and
• a wireless transceiver configured to facilitate near field communication (NFC) between the sensor device and an external device;
• wherein the wireless transceiver is configured to use power generated from NFC signals to transmit diagnostic data generated as a result of operating the flow sensor and the processing circuit over a past time period to the external device via direct NFC between the sensor device and the external device.

A method of configuring a flow sensor, the method comprising:

• wirelessly providing a configuration parameter comprising a setpoint from the flow sensor to an external device via direct NFC between the flow sensor and the external device using power generated from NFC signals, the flow sensor configured to sense a change in a characteristic of a fluid flow;
• receiving an update to the setpoint from the external device via NFC;
• updating a control program of the flow sensor with the update to the setpoint;
• and
• controlling operation of the flow sensor using the control program and the update to the setpoint.