Dual Evaporator Heat Pump Systems with Heat Recovery Source

Abstract

Vapor compression cycle systems having extra heating capacity are disclosed. The vapor compression cycle system includes a first heat exchanger that receives a first fluid (e.g., a refrigerant) from a compressor. A first flow control valve receives the first fluid from the first heat exchanger and directs a first portion of the fluid it towards a second heat exchanger and a second portion of the fluid towards a third heat exchanger. The third heat exchanger also receives a second fluid (e.g., hot water). The second heat exchanger outputs the first portion of the first fluid and third heat exchanger outputs the second portion of the first fluid. The first portion and the second portion of the first fluid is then directed back towards the compressor.

That which is claimed is: 
     
         1 . A method comprising:
 receiving, by a first heat exchanger, a first fluid from a compressor at a first port of the first heat exchanger;   outputting, by the first heat exchanger, the first fluid via a second port of the first heat exchanger;   receiving, by a first flow control valve, the first fluid from the first heat exchanger;   outputting, by the first flow control valve, a first portion of the first fluid towards a second heat exchanger;   outputting, by the first flow control valve, a second portion of the first fluid towards a third heat exchanger;   receiving, by the third heat exchanger, the second portion of the first fluid;   receiving, by the third heat exchanger, a second fluid;   outputting, by the second heat exchanger, the first portion of the first fluid;   outputting, by the third heat exchanger, the second portion of the first fluid; and   directing the first portion and the second portion of the first fluid towards the compressor.   
     
     
         2 . The method of  claim 1 , further comprising, prior to directing the first portion and the second portion of the first fluid towards the compressor, combining the first portion and the second portion of the first fluid. 
     
     
         3 . The method of  claim 1 , wherein receiving the second fluid further comprises receiving the second fluid from a heat source. 
     
     
         4 . The method of  claim 3 , wherein the heat source includes one of a gas hydronic boiler, an electric heater, or a solar heater. 
     
     
         5 . The method of  claim 1 , further comprising:
 outputting, by the third heat exchanger, the second fluid having a first temperature;   receiving, by the heat source, the second fluid having the first temperature;   outputting, by the heat source, the second fluid having a second temperature, wherein the second temperature is higher than the first temperature.   
     
     
         6 . The method of  claim 1 , wherein receiving the second fluid occurs at a first time and the second fluid has a first temperature at the first time, the method further comprising:
 receiving, by the third heat exchanger at a second time after the first time, the second fluid having a second temperature, wherein the second temperature is lower than the first temperature.   
     
     
         7 . The method of  claim 1 , further comprising:
 traversing a third fluid over the second heat exchanger, wherein the third fluid is air.   
     
     
         8 . A vapor compression cycle system comprising:
 a first heat exchanger;   a second heat exchanger;   a third heat exchanger;   a compressor; and   a heat source, wherein the vapor compression cycle system is operable to:   receive, at the first heat exchanger, a first fluid from the compressor;   receive, at the first heat exchanger, a second fluid from a facility;   receive, at the second heat exchanger, a first portion of the first fluid from the first heat exchanger;   receive, at the third heat exchanger, a second portion of the first fluid from the first heat exchanger;   receive, at the third heat exchanger, a third fluid from the heat source.   
     
     
         9 . The vapor compression cycle system of  claim 8 , further comprising a storage tank, wherein the vapor compression cycle system is further operable to:
 receive, at the storage tank, the second fluid from the first heat exchanger; and   receive, at the storage tank, the third fluid from the heat source.   
     
     
         10 . The vapor compression cycle system of  claim 8 , wherein:
 the second portion of the first fluid at a first port of the third heat exchanger has a first temperature; and   the second the second portion of the first fluid at a second port of the third heat exchanger has a second temperature that is higher than the first temperature.   
     
     
         11 . The vapor compression cycle system of  claim 10 , wherein:
 the third fluid has a first temperature at a third port of the third heat exchanger; and   the third fluid has a second temperature at a fourth port of the third heat exchanger, wherein the fourth temperature is lower than the third temperature.   
     
     
         12 . The vapor compression cycle system of  claim 10 , further comprising a flow control valve having four ports, wherein:
 a first port of the flow control valve is in fluid communication with the third port of the third heat exchanger;   a second port of the flow control valve is in fluid communication with the heat source;   a third port of the flow control valve is in fluid communication with a second flow control valve; and   a fourth port of the flow control valve is in fluid communication with a drain of a facility.   
     
     
         13 . The vapor compression cycle system of  claim 12 , wherein the second flow control valve is also in fluid communication with the heat source and the third port of the third heat exchanger. 
     
     
         14 . The vapor compression cycle system of  claim 12 , further comprising a variable speed pump coupled between the second flow control valve and the third heat exchanger. 
     
     
         15 . A method comprising:
 receiving, at a first port of a first heat exchanger, a first fluid;   outputting, via a second port of the first heat exchanger, the first fluid;   operating a first flow control valve to direct a first portion of the first fluid towards a first port of a second heat exchanger;   operating a second flow control valve to direct a first portion of a second fluid towards a second port of the second heat exchanger;   directing a second portion of the first fluid towards a third heat exchanger;   outputting the first portion of the first fluid via a third port of the second heat exchanger; and   outputting the first portion of the second fluid via a fourth port of the second heat exchanger.   
     
     
         16 . The method of  claim 15 , wherein:
 the first portion of the first fluid has a first temperature at the first port of a second heat exchanger and the first portion of the second fluid has as second temperature at the second port of the second heat exchanger; and   the first portion of the first fluid has a third temperature at the third port of the second heat exchanger and the first portion of the second fluid has as fourth temperature at the second port of the second heat exchanger, wherein the first temperature is lower than the second temperature and the third temperature is higher than the fourth temperature.   
     
     
         17 . The method of  claim 15 , further comprising:
 after exiting the fourth port of the second heat exchanger, directing the first portion of the second fluid towards a heat source.   
     
     
         18 . The method of  claim 15 , further comprising:
 directing a second portion of the first fluid towards a third heat exchanger;   outputting the second portion of the first fluid from the third heat exchanger; and   combining the second portion of the first fluid and the first portion of the first fluid after the first portion of the first fluid is outputted by the second heat exchanger and the second portion of the first fluid is outputted by the third heat exchanger.   
     
     
         19 . The method of  claim 15 , further comprising:
 receiving, by a heat source, the first portion of the second fluid from the fourth port of the second heat exchanger;   heating the first portion of the second fluid; and   directing the first portion of the second fluid back to the third port of the second heat exchanger.   
     
     
         20 . The method of  claim 15 , further comprising, prior to operating the first flow control valve to direct the first portion of the first fluid towards the first port of a second heat exchanger:
 determining that a first pressure of the first fluid at an input port of a compressor is lower than a threshold pressure value; or   determining that a first temperature of the first fluid at the input port of the compressor is lower than a threshold temperature value.