Systems and methods for heat pump systems for charge management

Abstract

Systems and methods for heating and cooling an interior space using a heat pump and an air duct system are provided. The heat pump system may be a split system with an indoor heat exchanger and an outdoor heat exchanger. The outdoor heat exchanger may have a volume capacity for holding a fluid such as refrigerant that is significantly larger than that of the indoor heat exchanger. In the heating cycle, the fluid may backup in the heat pump due to the difference in volume capacity between the heat exchangers. To accommodate the excess fluid, the heat pump may include a charge storage vessel. In one example, during a heating cycle, the charge storage vessel and the indoor coils may together serve as the condenser. The charge storage vessel may then prevent and/or relieve pressure build up in the compressor, which could negatively impact efficiency of the heat pump.

We claim: 
     
         1 . A heat pump system for charge management, the system comprising:
 a first plurality of coils configured to receive a fluid and exchange thermal energy with the fluid;   a blower in fluid communication with an exterior of the first plurality of coils;   a second plurality of coils configured to receive the fluid and exchange thermal energy with the fluid, the second plurality of coils having a first volume capacity larger than a second volume capacity of the first plurality of coils;   a compressor in fluid communication with the first plurality of coils and the second plurality of coils;   a charge storage vessel in fluid communication with the first plurality of coils and the second plurality of coils, the charge storage vessel configured to store a volume of the fluid, the charge storage vessel in fluid communication with a first expansion valve;   a first valve connected to the charge storage vessel at a first end of the charge storage vessel and a second valve connected to the charge storage vessel at a second end of the charge storage vessel, one or more of the first valve and the second valve configured to selectively transition to a closed position;   wherein the charge storage vessel is configured to exchange thermal energy with a fluid line extending between the second plurality of coils and the compressor, and   wherein the heat pump system is a ducted heat pump system or a packaged heat pump system.   
     
     
         2 . The heat pump system of  claim 1 , wherein the first valve is in fluid communication with the first plurality of coils and the second valve is in fluid communication with the second plurality of coils. 
     
     
         3 . The heat pump system of  claim 1 , wherein the first valve is a three-way valve and the second valve is a check valve and the first valve and the second valve are configured to cause the fluid to bypass the charge storage vessel in a cooling cycle. 
     
     
         4 . The heat pump system of  claim 2 , wherein the first valve is a three-way valve and the second valve is a check valve and the first valve and the second valve are configured to cause the fluid to pass through the charge storage vessel in a heating cycle. 
     
     
         5 . The heat pump system of  claim 4 , wherein the exchange of thermal energy between the fluid line and the charge storage vessel facilitates evacuation of fluid from the charge storage vessel when the heat pump system transitions from the heating cycle to the cooling cycle. 
     
     
         6 . The heat pump system of  claim 1 , wherein the first valve is a first three-way valve and the second valve is a second three-way valve and the first valve and the second valve are configured to cause the fluid to by-pass the charge storage vessel in a cooling cycle. 
     
     
         7 . The heat pump system of  claim 1 , wherein the first plurality of coils, the second plurality of coils, and the blower are positioned in a first housing and the second plurality of coils and the compressor are positioned in a second housing different than the first housing. 
     
     
         8 . The heat pump system of  claim 7 , wherein the first housing is configured to be positioned within a structure comprising the at least one air duct and the second housing is configured to be positioned outside the structure. 
     
     
         9 . The heat pump system of  claim 1 , wherein the blower is in fluid communication with at least one air duct. 
     
     
         10 . The heat pump system of  claim 1 , wherein the second plurality of coils and the first plurality of coils the have a volume capacity ratio of greater than 2:1. 
     
     
         11 . A heat pump system for charge management, the system comprising:
 a first plurality of coils configured to receive a fluid and exchange thermal energy with the fluid;   a blower in fluid communication with an exterior of the first plurality of coils;   a second plurality of coils configured to receive the fluid and exchange thermal energy with the fluid, the second plurality of coils having a first volume capacity larger than a second volume capacity of the first plurality of coils;   a compressor in fluid communication with the first plurality of coils and the second plurality of coils;   a charge storage vessel in fluid communication with the first plurality of coils and the second plurality of coils, the charge storage vessel configured to store a volume of the fluid, the charge storage vessel in fluid communication with an expansion valve;   a first valve in fluid communication with a first end of the charge storage vessel;   a second valve in fluid communication with a second end of the charge storage vessel; and   a bleeder cap tube between the first valve and the first plurality of coils, and wherein the heat pump system is a ducted heat pump system or a packaged heat pump system.   
     
     
         12 . The heat pump system of  claim 11 , wherein the first valve is a first solenoid valve and the second valve is a second solenoid valve. 
     
     
         13 . The heat pump system of  claim 12 , wherein fluid is permitted to evacuate the charge storage vessel via the bleeder cap tube. 
     
     
         14 . The heat pump system of  claim 11 , wherein the blower is in fluid communication with at least one air duct. 
     
     
         15 . The heat pump system of  claim 11 , further comprising the first expansion valve positioned between the charge storage vessel and the plurality of second coils. 
     
     
         16 . The heat pump system of  claim 15 , further comprising a second expansion valve positioned between the second plurality of coils and the charge storage vessel. 
     
     
         17 . The heat pump system of  claim 11 , wherein the second plurality of coils and the first plurality of coils the have a volume capacity ratio of greater than 2:1. 
     
     
         18 . The heat pump system of  claim 11 , wherein the wherein the first plurality of coils, the charge storage vessel, and the blower are positioned in a first housing. 
     
     
         19 . The heat pump system of  claim 18 , wherein the second plurality of coils and the compressor are positioned in the first housing. 
     
     
         20 . The heat pump system of  claim 18 , wherein the second plurality of coils and the compressor are positioned in a second housing different than the first housing.