Multi-stage air handling unit for linear capacity output

Abstract

There is disclosed a multi-stage air handling unit for linear capacity output comprising condenser coils, expansion valves, evaporator coils, and compressors. The condenser coils convert a refrigerant from a gas state to a liquid state to transfer heat to a first air medium. The expansion valves decrease pressure in the refrigerant. The evaporator coils convert the refrigerant from the liquid state to the gas state to transfer heat from a second air medium. The compressors increase pressure in the refrigerant and provide the linear capacity output. The compressors consist of one variable capacity compressor and at least one constant capacity compressor. For other aspects, data associated a multi-stage air handling unit is collected, a scroll compressor may be identified, the air handling unit is converted, a multi-stage compressor may be determined, and multiple states of the compressors are operated as linear capacity output.

What is claimed is: 
     
         1 . A multi-stage air handling unit for linear capacity output comprising:
 a plurality of condenser coils supported by the multi-stage air handling unit, the plurality of condenser coils to convert a refrigerant from a gas state to a liquid state to transfer heat, to a first air medium;   a plurality of expansion valves coupled to the plurality of condenser coils, the plurality of expansion valves to decrease pressure in the refrigerant;   a plurality of evaporator coils coupled to the plurality of expansion valves, the plurality of evaporator coils to convert the refrigerant from the liquid state to the gas state to transfer heat from a second air medium; and   a plurality of compressors coupled to the plurality of evaporator coils; the plurality of compressors to increase pressure in the refrigerant and provide the linear capacity output, the plurality of compressors consist of one variable capacity compressor and at least one constant capacity compressor.   
     
     
         2 . The multi-stage air handling unit as described in  claim 1 , wherein the at least one constant capacity compressor includes a single stage control device, and the variable capacity compressor includes a multi-stage control device. 
     
     
         3 . The multi-stage air handling unit as described in  claim 2 , wherein the multi-stage control device is a variable frequency drive. 
     
     
         4 . The multi-stage air handling unit as described in  claim 1 , further comprising a housing to support the plurality of condenser coils, the plurality of expansion valves, the plurality of evaporator coils, and the plurality of compressors, wherein:
 the housing includes a compartment for the plurality of compressors; and   the variable capacity compressor is a replacement that substantially fits within an area of the compartment previously occupied by an original constant capacity compressor.   
     
     
         5 . The multi-stage air handling unit as described in  claim 1 , further comprising a housing to support the plurality of condenser coils, the plurality of expansion valves, the plurality of evaporator coils, and the plurality of compressors, wherein:
 the housing includes a compartment for a multi-stage control device to drive the variable capacity compressor; and   the multi-stage control device is a replacement that substantially fits within an area of the compartment previously occupied by an original multi-stage control device.   
     
     
         6 . The multi-stage air handling unit as described in  claim 1 , wherein:
 the plurality of condenser coils include a first condenser coil and a second condenser coil;   the plurality of expansion valves include a first expansion valve and a second expansion valve, the first expansion valve coupling to the first condenser coil and the second expansion valve coupling to the second condenser coil;   the plurality of evaporator coils include a first evaporator coil and a second evaporator coil, the first evaporator coil coupling to the first expansion valve and the second evaporator coil coupling to the second expansion valve;   the one variable capacity compressor coupling to the first evaporator coil; and   a particular constant capacity compressor of the at least one constant capacity compressor coupling to the second evaporator coil.   
     
     
         7 . A system for analyzing a multi-stage air handling unit for linear capacity output comprising:
 an input component collecting data associated with the multi-stage air handling unit having a plurality of compressors; and   a processor coupled to the input component, the processor identifying whether the plurality of compressors of the air handling unit include a scroll compressor based on the collected data and determining whether the plurality of compressors include a multi-stage compressor subsequent to converting the air handling unit; and   an output component coupled to the processor, the output component signaling one or more remote devices to convert the air handling unit based on whether the plurality of compressors include the multi-state compressor and operate multiple stages of the plurality of compressors as linear capacity output subsequent to converting the air handling unit.   
     
     
         8 . The system as described in  claim 7 , wherein the output component signals the one or more remote devices to convert a single-stage compressor of the plurality of compressors to the multi-stage compressor. 
     
     
         9 . The system as described in  claim 7 , wherein:
 the processor determines that all compressors of the plurality of compressors are single-stage compressors; and   the output component signals the one or more remote devices to convert a particular single-stage compressor of the single-stage compressors to the multi-stage compressor in response to determining that all compressors of the plurality of compressors are the single-stage compressors.   
     
     
         10 . The system as described in  claim 7 , wherein the output component signals the one or more remote devices to setup a variable frequency drive based on a compressor voltage and a compressor horsepower. 
     
     
         11 . The system as described in  claim 7 , wherein the output component signals the one or more remote devices to operate each single-stage compressor of the plurality of single-stage compressors for a predetermined capacity range and operate the multi-stage compressor for at least a portion of each predetermined capacity range. 
     
     
         12 . The system as described in  claim 7 , wherein the output component signals the one or more remote devices to:
 operate the multiple stages of the plurality of compressors as the linear capacity output based on a first control strategy subsequent to converting the air handling unit, the first control strategy being associated with a determination that the plurality of compressors do not include the multi-stage compressor; and   operate the multiple stages of the plurality of compressors as the linear capacity output based on a second control strategy subsequent to converting the air handling unit, the second control strategy being associated with a determination that the plurality of compressors include at least one multi-stage compressor,   wherein the second control strategy is different from the first control strategy.   
     
     
         13 . The system as described in  claim 7 , wherein:
 the processor identifies an independent refrigeration circuit associated with the plurality of compressors based on the collected data; and   the output component signals the one or more remote devices to:
 operate the multiple stages of the plurality of compressors as the linear capacity output based on a first control strategy subsequent to converting the air handling unit, the first control strategy being associated with identifying the independent refrigeration circuit; and 
 operate the multiple stages of the plurality of compressors as the linear capacity output based on a second control strategy subsequent to converting the air handling unit, the second control strategy being associated with an inability to identify the independent refrigeration circuit, 
 wherein the second control strategy is different from the first control strategy. 
   
     
     
         14 . A method for analyzing a multi-stage air handling unit for linear capacity output, the method comprising:
 collecting data associated with the multi-stage air handling unit having a plurality of compressors;   identifying whether the plurality of compressors of the air handling unit include a scroll compressor based on the collected data;   converting the air handling unit based on whether the plurality of compressors include a multi-stage compressor;   determining whether the plurality of compressors include the multi-stage compressor subsequent to converting the air handling unit; and   operating multiple stages of the plurality of compressors as linear capacity output in response to determining whether the plurality of compressors include the multi-stage compressor.   
     
     
         15 . The method as described in  claim 14 , wherein converting the air handling unit includes converting a single-stage compressor of the plurality of compressors to the multi-stage compressor. 
     
     
         16 . The method as described in  claim 14 , wherein converting the air handling unit comprises converting a particular single-stage compressor of the single-stage compressors to the multi-stage compressor in response to determining that all compressors of the plurality of compressors are the single-stage compressors. 
     
     
         17 . The method as described in  claim 14 , wherein:
 converting the air handling unit includes setting-up a variable frequency drive based on a compressor voltage and a compressor horsepower.   
     
     
         18 . The method as described in  claim 14 , wherein operating the multiple stages of the plurality of compressors includes operating each single-stage compressor of the plurality of single-stage compressors for a predetermined capacity range and operating the multi-stage compressor for at least a portion of each predetermined capacity range. 
     
     
         19 . The method as described in  claim 14 , wherein operating the multiple stages of the plurality of compressors includes:
 operating the multiple stages of the plurality of compressors as the linear capacity output based on a first control strategy subsequent to converting the air handling unit, the first control strategy being associated with a determination that the plurality of compressors do not include the multi-stage compressor; and   operating the multiple stages of the plurality of compressors as the linear capacity output based on a second control strategy subsequent to converting the air handling unit, the second control strategy being associated with a determination that the plurality of compressors include at least one multi-stage compressor,   wherein the second control strategy is different from the first control strategy.   
     
     
         20 . The method as described in  claim 14 , further comprising identifying an independent refrigeration circuit associated with the plurality of compressors based on the collected data, wherein operating the multiple stages of the plurality of compressors includes:
 operating the multiple stages of the plurality of compressors as the linear capacity output based on a first control strategy subsequent to converting the air handling unit, the first control strategy being associated with identifying the independent refrigeration circuit; and   operating the multiple stages of the plurality of compressors as the linear capacity output based on a second control strategy subsequent to converting the air handling unit, the second control strategy being associated with an inability to identify the independent refrigeration circuit,   wherein the second control strategy is different from the first control strategy.