Method and Apparatus for Monitoring Refrigeration-Cycle Systems

Abstract

A monitoring system is disclosed for a heating, ventilation, or air conditioning (HVAC) system of a residential or commercial building. The monitoring system includes an evaporator unit device including a first current sensor that measures current supplied to a circulator blower. The measured current from the first current sensor is used to diagnose a problem with the circulator blower. The monitoring system includes a first temperature sensor that measures refrigerant temperature between a condenser and an expansion valve. The monitoring system includes a second temperature sensor that measures refrigerant temperature between an evaporator and a compressor. The monitoring system includes a condenser unit device that communicates with the evaporator unit device. The condenser unit device includes a second current sensor that measures current supplied to the compressor. The evaporator unit device transmits sensor data to a remote monitoring service over a data network.

What is claimed is: 
     
         1 . A monitoring system for a heating, ventilation, or air conditioning (HVAC) system of a residential or commercial building, the monitoring system comprising:
 an evaporator unit device including a first electrical sensor that measures current supplied to a circulator blower of the HVAC system, wherein the measured current from the first electrical sensor is used to diagnose a problem with the circulator blower;   a first temperature sensor that measures a temperature of refrigerant flowing between a condenser of the HVAC system and an expansion valve of the HVAC system;   a second temperature sensor that measures a temperature of refrigerant flowing between an evaporator of the HVAC system and a compressor of the HVAC system;   a third temperature sensor that measures a temperature of air flowing away from the evaporator; and   a fourth temperature sensor that measures a temperature of air flowing toward the evaporator,   wherein the evaporator unit device transmits sensor data to a remote monitoring service over a data network.