Monitoring and recoverable protection of thermostat switching circuitry

A method of automated sensing of an anomalous wiring condition associated with a thermostat, the method comprising:

• switching on a field effect transistor within the thermostat, the field effect transistor and associated circuitry configured to turn on an HVAC function;
• monitoring one or more electrical properties associated with the field effect transistor;
• determining if an anomalous wiring condition is associated with the field effect transistor based at least in part on the monitored one or more electrical properties;
• and
• in cases where it is determined that an anomalous wiring condition is associated with the field effect transistor:
• switching off the field effect transistor;
• determining whether the thermostat can be operated by re-purposing one or more thermostat components;
• and
• in cases where it is determined that the thermostat can be so operated, re-purposing the one or more thermostat components.

A method of automated monitoring of a protection fuse within a thermostat, the method comprising:

• measuring voltages associated with first and second terminals of the protection fuse, wherein the protection fuse is connected to an HVAC function control circuit configured to turn on and off an HVAC function such that the protection fuse blows when the HVAC function control circuit experiences excessive current;
• automatically detecting with a microprocessor within the thermostat whether the fuse is in a blown state based on the measured electrical properties;
• and
• in cases where the microprocessor detects the fuse in a blown state:
• writing data to a memory indicating the detected blown state of the fuse;
• determining whether the thermostat can be operated by re-purposing one or more thermostat components;
• in cases where it is determined that the thermostat can be so operated, re-purposing the one or more thermostat components;
• displaying an error message on a display of the thermostat indicating that the fuse is blown;
• causing information to be transmitted to a manufacturer of the thermostat indicating that the fuse is blown, the information facilitating a diagnosis performed by the manufacturer of potential problems associated with the thermostat;
• and
• displaying a message offering assistance to a user of the thermostat based in part on the diagnosis performed by the manufacturer of potential problems associated with the thermostat.