Abstract: A method of determining loss of refrigerant charge in a heating, ventilation, and air conditioning (HVAC) system. The method includes receiving, using a controller, a plurality of temperature values from a plurality of temperature sensors placed at multiple locations within the HVAC system and calculating, using the controller using the plurality of temperature values, a plurality of temperature-dependent values. The method further includes determining, using the controller, whether a first temperature-dependent value of the plurality of temperature-dependent values is above a first predetermined temperature value and responsive to a determination that the first temperature-dependent value is above the first predetermined temperature value, transmitting, using the controller to a user interface, a notification indicating that the HVAC system is operating with low refrigerant charge.

Abstract: A method of determining loss of refrigerant charge in a heating, ventilation, and air conditioning (HVAC) system. The method includes receiving, using a controller, a plurality of temperature values from a plurality of temperature sensors placed at multiple locations within the HVAC system and calculating, using the controller using the plurality of temperature values, a plurality of temperature-dependent values. The method further includes determining, using the controller, whether a first temperature-dependent value of the plurality of temperature-dependent values is above a first predetermined temperature value and responsive to a determination that the first temperature-dependent value is above the first predetermined temperature value, transmitting, using the controller to a user interface, a notification indicating that the HVAC system is operating with low refrigerant charge.

Abstract: A method of determining loss of refrigerant charge in a heating, ventilation, and air conditioning (HVAC) system. The method includes receiving, using a controller, a plurality of temperature values from a plurality of temperature sensors placed at multiple locations within the HVAC system and calculating, using the controller using the plurality of temperature values, a plurality of temperature-dependent values. The method further includes determining, using the controller, whether a first temperature-dependent value of the plurality of temperature-dependent values is above a first predetermined temperature value and responsive to a determination that the first temperature-dependent value is above the first predetermined temperature value, transmitting, using the controller to a user interface, a notification indicating that the HVAC system is operating with low refrigerant charge.

Abstract: A method of determining loss of refrigerant charge in a heating, ventilation, and air conditioning (HVAC) system. The method includes receiving, using a controller, a plurality of temperature values from a plurality of temperature sensors placed at multiple locations within the HVAC system and calculating, using the controller using the plurality of temperature values, a plurality of temperature-dependent values. The method further includes determining, using the controller, whether a first temperature-dependent value of the plurality of temperature-dependent values is above a first predetermined temperature value and responsive to a determination that the first temperature-dependent value is above the first predetermined temperature value, transmitting, using the controller to a user interface, a notification indicating that the HVAC system is operating with low refrigerant charge.

Abstract: An HVAC unit includes an HVAC motor and a system controller. The HVAC motor is coupled to a motor controller. The motor controller is configured to receive a command signal bearing a digitally encoded operating level of the HVAC motor. The system controller is coupled to the motor controller, and is configured to transmit the command signal to the motor controller. The system controller modulates the command signal with the digitally encoded operating level in response to a service demand.

Abstract: An HVAC unit includes an HVAC motor and a system controller. The HVAC motor is coupled to a motor controller. The motor controller is configured to receive a command signal bearing a digitally encoded operating level of the HVAC motor. The system controller is coupled to the motor controller, and is configured to transmit the command signal to the motor controller. The system controller modulates the command signal with the digitally encoded operating level in response to a service demand.