Tracking and evaluating the performance of a HVAC system

A process for monitoring performance of at least one mode of an HVAC system using information from a thermostat for that HVAC system, the process comprising:

• periodically storing in memory, information that includes:
• current mode of operation for the HVAC system;
• and
• whether the HVAC system is active or idle
• upon detection that the HVAC system has completed a runtime in heat mode, create a heat performance tuple that includes:
• a heat ΔT value that equals a difference in temperature between a thermostat set point for the HVAC system in heat mode and a particular value representative of an air temperature outside a building that the HVAC system is servicing;
• and
• a heating runtime percentage based on a percentage of stored values that indicate that the HVAC system was active taken over a heating lookback period that ends with an end of a most recent heat runtime;
• storing the heat performance tuple along with a date and a time for the end of the most recent heat runtime;
• and
• wherein the heat performance tuple is converted into a heat performance metric so that a recently stored heat performance metric may be compared with at least one previously stored heat performance metric from at least one heat performance tuple with a ΔT different from the heat performance tuple used to create the recently stored heat performance metric;
• and
• upon detection that the HVAC system is running in cool mode, create a cool performance tuple that includes:
• a cool ΔT value that equals a difference in temperature between a specific value representative of an air temperature outside the building and a thermostat set point for the HVAC system in cool mode;
• a cooling runtime percentage based on a percentage of stored values that indicate that the HVAC system was active taken over a cooling lookback period that ends with an end of the most recent cool runtime;
• and
• storing the cool performance tuple along with a date and time for the end of the most recent cool runtime;
• and
• wherein the cool performance tuple is converted into a cool performance metric so that a recently stored cool performance metric may be compared with at least one previously stored cool performance metric from at least one cool performance tuple with a ΔT different from the cool performance tuple used to create the recently stored cool performance metric.

A monitoring device for monitoring a heat performance of an HVAC system, the monitoring device comprising:

• a processor for executing instructions and moving information from one component to another component;
• a memory for storing instructions for execution by the processor and for storing data;
• a temperature sensor for measuring an air temperature at the monitoring device;
• a means for obtaining an outdoor air temperature for air outside of a building containing the monitoring device;
• a means for communicating to an Internet connected storage location;
• the monitoring device having instructions to enable the monitoring device to:
• periodically store the air temperature provided by the temperature sensor;
• detect that a most recently obtained air temperature is higher than a set of at least one recently stored air temperatures and deeming that to be an indication that the HVAC heat system is on;
• and
• detect that the most recently obtained air temperature is not higher than a set of at least one recently stored air temperature and deeming that to be an indication that the HVAC heat system is idle;
• after detecting that the HVAC heat system became idle after a period of time when the HVAC heat system was on, create a heat performance tuple that includes:
• a heat ΔT value that equals a difference in temperature between a temperature where the HVAC system became idle after being on and a value representative of an air temperature outside the building;
• and
• a runtime percentage based on the percentage of the obtained temperatures that indicated that the HVAC heat system was on over a lookback period that ends a most recent instance of the HVAC heat system becoming idle after a period of time when the HVAC heat system was on;
• and
• storing the heat performance tuple along with a date and time for the most recent instance of the HVAC heat system becoming idle after a period of time when the HVAC heat system was on.