A temperature monitor and control system, comprising: a battery-operated temperature monitoring device (102A - 102D) located within a structure, and wirelessly coupled to a network of the system; a thermostat remote from said temperature monitoring device (102A - 102D) configured to regulate a heating, ventilation, and air conditioning, HVAC, system within the structure; said thermostat coupled to said network and having a processor, a temperature sensor and a memory comprising computer-readable instructions; said processor configured to execute said instructions to: wirelessly receive a first temperature from said temperature monitoring device (102A - 102D); obtain a second temperature from said thermostat temperature sensor; characterized by instructions to: determine an offset temperature based on a difference between said first temperature and said second temperature by computing the difference between the second temperature of the thermostat temperature sensor and the first temperature of the temperature monitoring device (102A-102D); apply said offset temperature to said thermostat to cause said thermostat to regulate said HVAC system in view of said first temperature; override said applied offset temperature in response to a determination that a fail-safe condition is met, wherein the determination is based on a difference between a current set point of the thermostat and the second temperature from said thermostat temperature sensor exceeding a temperature value; and cause the thermostat to revert to regulating the HVAC system in view of the second temperature sensed by the thermostat temperature sensor. a battery-operated temperature monitoring device (102A - 102D) located within a structure, and wirelessly coupled to a network of the system; a thermostat remote from said temperature monitoring device (102A - 102D) configured to regulate a heating, ventilation, and air conditioning, HVAC, system within the structure; said thermostat coupled to said network and having a processor, a temperature sensor and a memory comprising computer-readable instructions; said processor configured to execute said instructions to: wirelessly receive a first temperature from said temperature monitoring device (102A - 102D); obtain a second temperature from said thermostat temperature sensor; characterized by instructions to: determine an offset temperature based on a difference between said first temperature and said second temperature by computing the difference between the second temperature of the thermostat temperature sensor and the first temperature of the temperature monitoring device (102A-102D); apply said offset temperature to said thermostat to cause said thermostat to regulate said HVAC system in view of said first temperature; override said applied offset temperature in response to a determination that a fail-safe condition is met, wherein the determination is based on a difference between a current set point of the thermostat and the second temperature from said thermostat temperature sensor exceeding a temperature value; and cause the thermostat to revert to regulating the HVAC system in view of the second temperature sensed by the thermostat temperature sensor. wirelessly receive a first temperature from said temperature monitoring device (102A - 102D); obtain a second temperature from said thermostat temperature sensor; characterized by instructions to: determine an offset temperature based on a difference between said first temperature and said second temperature by computing the difference between the second temperature of the thermostat temperature sensor and the first temperature of the temperature monitoring device (102A-102D); apply said offset temperature to said thermostat to cause said thermostat to regulate said HVAC system in view of said first temperature; override said applied offset temperature in response to a determination that a fail-safe condition is met, wherein the determination is based on a difference between a current set point of the thermostat and the second temperature from said thermostat temperature sensor exceeding a temperature value; and cause the thermostat to revert to regulating the HVAC system in view of the second temperature sensed by the thermostat temperature sensor. determine an offset temperature based on a difference between said first temperature and said second temperature by computing the difference between the second temperature of the thermostat temperature sensor and the first temperature of the temperature monitoring device (102A-102D); apply said offset temperature to said thermostat to cause said thermostat to regulate said HVAC system in view of said first temperature; override said applied offset temperature in response to a determination that a fail-safe condition is met, wherein the determination is based on a difference between a current set point of the thermostat and the second temperature from said thermostat temperature sensor exceeding a temperature value; and cause the thermostat to revert to regulating the HVAC system in view of the second temperature sensed by the thermostat temperature sensor.