Testing a heat detector of a self-testing hazard sensing device

A method of operating a self-testing hazard sensing device, comprising:

• providing, by a controller having a memory and processor, energy to a heat detector of the self-testing hazard sensing device;
• determining, by the controller after providing the energy to the heat detector, an amount of time it takes for the heat detector to cool to a threshold temperature;
• determining, by the controller, whether the amount of time it takes for the heat detector to cool to the threshold temperature meets or exceeds a threshold amount of time;
• and
• determining, by the controller, whether the heat detector is functioning properly based on whether the amount of time it takes for the heat detector to cool to the threshold temperature meets or exceeds the threshold amount of time.

A self-testing hazard sensing device, comprising:

• a heat detector;
• and
• a controller having a memory and a processor to:
• provide energy to the heat detector to heat the heat detector to a first threshold temperature;
• determine, after the heat detector has heated to the first threshold temperature, an amount of time it takes for the heat detector to cool from the first threshold temperature to a second threshold temperature;
• determine whether the amount of time it takes for the heat detector to cool to the second threshold temperature meets or exceeds a threshold amount of time;
• and
• determine whether the heat detector is functioning properly based on whether the amount of time it takes for the heat detector to cool to the second threshold temperature meets or exceeds the threshold amount of time.