Systems and Methods for Interlaced Microchannel Heat Exchanger Systems with Multiple Compressors of Different Sizes

Abstract

Systems and methods for multi-circuit air systems have been developed that include a plurality of fluidly separated refrigerant circuits. Each of the refrigerant circuits may flow through a single indoor heat exchanger (e.g., evaporator) and a single outdoor heat exchanger (e.g., condenser). The refrigerant may be selectively and independently flowed through each individual refrigerant circuit. Each refrigerant circuit may include a compressor, which may have different sizes. The heat outdoor and/or indoor heat exchangers may be interlaced microchannel heat exchangers designed to accommodate different refrigerant charge quantities in the different refrigerant circuits. The interlaced heat changers may include alternating rows connected to the different refrigerant circuits to efficiently exchange thermal energy across the entire heat exchanger.

We claim: 
     
         1 . A system comprising: 
 a first interlaced microchannel heat exchanger comprising a first plurality of passages and a second plurality of passages;   a second interlaced microchannel heat exchanger comprising a third plurality of passages and a fourth plurality of passages;   a first refrigerant circuit comprising a first compressor and a first thermal expansion valve, the first refrigerant circuit coupled to the first plurality of passages of the first interlaced microchannel heat exchanger and the third plurality of passages of the second interlaced microchannel heat exchanger; and   a second refrigerant circuit comprising a second compressor and a second thermal expansion valve, the second refrigerant circuit coupled to the second plurality of passages of the first interlaced microchannel heat exchanger and the fourth plurality of passages of the second interlaced microchannel heat exchanger, the second compressor having a larger size than the first compressor,   wherein the first plurality of passages are positioned between with the second plurality of passages in the first interlaced microchannel heat exchanger.   
     
     
         2 . The system of  claim 1 , wherein the first plurality of passages is disposed within a first plurality of rows and the second plurality of passages is disposed within a second plurality of rows. 
     
     
         3 . The system of  claim 2 , wherein the second plurality of rows are interspersed between the first plurality of rows. 
     
     
         4 . The system of  claim 2 , wherein the second plurality of passages comprises a greater number of passages than the first plurality of passages. 
     
     
         5 . The system of  claim 2 , wherein the second plurality of rows corresponds to a second amount of rows that is greater than a first amount of rows corresponding to the first plurality of rows. 
     
     
         6 . The system of  claim 2 , wherein the first interlaced microchannel heat exchanger comprises at least twice as many of the second plurality of rows than the first plurality of rows. 
     
     
         7 . The system of  claim 1 , wherein the first refrigerant circuit is configured to receive a first volume of refrigerant and the second refrigerant circuit is configured to receive a second volume of refrigerant, and wherein the second volume of refrigerant is greater than the first volume of refrigerant. 
     
     
         8 . The system of  claim 1 , wherein the first refrigerant circuit is not in fluid communication with the second refrigerant circuit. 
     
     
         9 . The system of  claim 1 , wherein one or more of the first compressor or the second compressor is a multi-stage compressor. 
     
     
         10 . The system of  claim 1 , wherein the first compressor is configured to operate while the second compressor is non-operational. 
     
     
         11 . A system comprising: 
 a first interlaced microchannel heat exchanger comprising a first plurality of passages and a second plurality of passages;   a second interlaced microchannel heat exchanger comprising a third plurality of passages and a fourth plurality of passages;   a first refrigerant circuit comprising a first compressor and a first thermal expansion valve, the first refrigerant circuit coupled to the first plurality of passages of the first interlaced microchannel heat exchanger and the third plurality of passages of the second interlaced microchannel heat exchanger; and   a second refrigerant circuit comprising a second compressor and a second thermal expansion valve, the second refrigerant circuit coupled to the second plurality of passages of the first interlaced microchannel heat exchanger and the fourth plurality of passages of the second interlaced microchannel heat exchanger, the second compressor have a larger size than the first compressor,   wherein each passage of the first plurality of passages has a first cross-sectional area and each passage of the second plurality of passages has a second cross-sectional area larger than the first cross-sectional area.   
     
     
         12 . The system of  claim 11 , wherein the first plurality of passages is disposed within a first plurality of rows and the second plurality of passages is disposed within a second plurality of rows. 
     
     
         13 . The system of  claim 12 , wherein the second plurality of rows are interspersed between the first plurality of rows. 
     
     
         14 . The system of  claim 12 , wherein the second plurality of passages comprises a greater number of passages than the first plurality of passages. 
     
     
         15 . The system of  claim 12 , wherein the first interlaced microchannel heat exchanger comprises plurality of rows and each row of the plurality of rows comprises at least one passage of the plurality of first passages and at least one passage of the plurality of second passages. 
     
     
         16 . The system of  claim 12 , wherein the second plurality of rows corresponds to a second amount of rows that is greater than a first amount of rows corresponding to the first plurality of rows. 
     
     
         17 . The system of  claim 11 , wherein the first refrigerant circuit is configured to receive a first volume of refrigerant and the second refrigerant circuit is configured to receive a second volume of refrigerant, and wherein the second volume of refrigerant is greater than the first volume of refrigerant. 
     
     
         18 . The system of  claim 11 , wherein the first refrigerant circuit is not in fluid communication with the second refrigerant circuit. 
     
     
         19 . The system of  claim 11 , wherein one or more of the first compressor or the second compressor is a multi-stage compressor. 
     
     
         20 . The system of  claim 11 , wherein the first compressor is configured to operate while the second compressor is non-operational.