Patent ID: 11965664
Assignee: TYCO FIRE & SECURITY GMBH
Field: Thermal processes and apparatus (Mechanical engineering)
Classification: CPC F  G | IPC F  G

Claim 0:
1. A controller for monitoring building efficiency of a heating, ventilation, and air conditioning (HVAC) system, comprising:
a memory configured to store a set of instructions; and
at least one processor coupled to the memory and configured to execute the set of instructions, wherein the at least one processor is further configured to:
establish a current building efficiency state value of a current run cycle of the HVAC system, wherein the current building efficiency state value is based on a first building efficiency reference value corresponding to a beginning of the current run cycle and a second building efficiency reference value corresponding to an end of the current run cycle, the first building efficiency reference value is based at least in part on a first temperature difference value between a first supply temperature value and a first return temperature value at the beginning of the current run cycle of the HVAC system, the second building efficiency reference value is based at least in part on a second temperature difference value between a second supply temperature value and a second return temperature value at the end of the current run cycle of the HVAC system, the current building efficiency state value is further based on an average of the first temperature difference value and the second temperature difference value and based on a constant value and an airflow value of the HVAC system, and the current building efficiency state value is determined according to a product of the constant value and the average of the first temperature difference value and the second temperature difference value multiplied by the airflow value;
determine a building efficiency state deviation value based on a difference between an average building efficiency state value of a set of previous building efficiency state values and the current building efficiency state value, wherein the average building efficiency state value of the set of previous building efficiency state values corresponds to a running average of a previous number of building efficiency state values, wherein each previous building efficiency state value of the set of previous building efficiency state values is associated with a respective, distinct run cycle;
determine whether the building efficiency state deviation value satisfies a building inefficiency threshold; and
provide an indication including an inefficiency status to a device associated with the HVAC system based on a determination that the current building efficiency state satisfies the building inefficiency threshold.