Portable method and apparatus for monitoring refrigerant-cycle systems

Abstract

A portable monitoring system that monitors various aspects of the operation of a refrigerant-cycle system is described. In one embodiment, the system includes a processor that measures power provided to the refrigerant-cycle system and gathers data from one or more sensors and uses the sensor data to calculate a figure of merit related to the efficiency of the system. In one embodiment, the measurements performed by the monitoring system include one or more of: an evaporator input air temperature, an evaporator output air temperature, evaporator air flow, evaporator air humidity, condenser air input temperature, condenser air output temperature sensor, electrical power. In one embodiment, the portable monitoring system receives information about the refrigerant-cycle system from either the system itself or from a computer network.

1 . A monitoring system for monitoring the operation of a refrigerant-cycle system, comprising:
 a monitoring unit comprising a processing system, a display, and one or more user input devices;   an airflow sensor provided to said monitoring unit;   a power sensor provided to said monitoring unit;   a temperature sensor provided to said monitoring unit; and   a network interface provided to said monitoring units, said monitoring unit using said network interface to query and receive performance information regarding an HVAC unit identified by a model number, said performance information comprising information related to an expected efficiency of said HVAC unit as a function of ambient temperature, said monitoring unit using airflow data received from said airflow sensor, power data received from said power sensor, and temperature data received from said temperature sensor to compute a current efficiency of said HVAC unit, said monitoring unit using said display to display a relationship between said current efficiency and said expected efficiency.   
   
   
       2 . The monitoring system of  claim 1 , wherein said processing system is configured to calculate energy usage. 
   
   
       3 . The monitoring system of  claim 1 , wherein said processing system is configured to calculate energy costs due to inefficient operation of said refrigerant-cycle system. 
   
   
       4 . The monitoring system of  claim 1 , wherein said processing system is configured to identify performance problems due to low airflow. 
   
   
       5 . The monitoring system of  claim 1 , wherein said processing system is configured to identify performance problems due to excessive load. 
   
   
       6 . The monitoring system of  claim 1 , wherein said processing system is configured to identify performance problems due to refrigerant undercharge. 
   
   
       7 . The monitoring system of  claim 1 , wherein said processing system is configured to identify performance problems due to refrigerant overcharge. 
   
   
       8 . The monitoring system of  claim 1 , wherein said one or more user input devices comprise a touch screen. 
   
   
       9 . The monitoring system of  claim 1 , wherein said one or more user input devices comprise a keypad. 
   
   
       10 . The monitoring system of  claim 1 , wherein said one or more user input devices comprise a microphone. 
   
   
       11 . The monitoring system of  claim 1 , wherein said processing system is configured to identify performance problems due to inefficient compressor operation. 
   
   
       12 . The monitoring system of  claim 1 , wherein said processing system is configured to provide data for plots of energy usage and costs. 
   
   
       13 . The monitoring system of  claim 1 , wherein said processing system is configured to provide data related to operation of said refrigerant-cycle system to a remote monitoring center. 
   
   
       14 . The monitoring system of  claim 1 , wherein said network interface communicates with an RFID tag of said HVAC unit to obtain information related to an expected efficiency. 
   
   
       15 . The monitoring system of  claim 1 , wherein said network interface communicates with said HVAC unit to obtain information related to an expected efficiency. 
   
   
       16 . The monitoring system of  claim 1 , wherein said monitoring unit communicates with said power sensor via wireless communication. 
   
   
       17 . The monitoring system of  claim 1 , wherein said monitoring system is configured with data regarding a maximum expected efficiency for the HVAC unit. 
   
   
       18 . The monitoring system of  claim 1 , wherein said monitoring system is configured with data regarding a type of refrigerant used in the HVAC unit. 
   
   
       19 . The monitoring system of  claim 1 , wherein said monitoring system is configured with data regarding the characteristics of the condenser. 
   
   
       20 . The monitoring system of  claim 1 , wherein said monitoring system is configured with data regarding the characteristics of the evaporator. 
   
   
       21 . The monitoring system of  claim 1 , wherein said monitoring unit communicates with said temperature sensor via wireless communication. 
   
   
       22 . The monitoring system of  claim 1 , wherein said monitoring unit communicates with said airflow sensor via wireless communication. 
   
   
       23 . The monitoring system of  claim 1 , further comprising a humidity sensor. 
   
   
       24 . The monitoring system of  claim 1 , wherein said airflow sensor is provided to an adapter to adapt said airflow sensor to an exhaust vent of said HVAC unit. 
   
   
       25 . The monitoring system of  claim 1 , wherein said airflow sensor is provided to an adapter to adapt said airflow sensor to an intake vent of said HVAC unit.