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US 6,826,921 B1Granted
Air conditioning system with variable condenser reheat for enhanced dehumidification
AssigneeLennox Industries Inc.
InventorRobert B. Uselton
Life of this patent
Estimating the term…
Abstract
A vapor compression air conditioning system, including a heat pump embodiment, provides enhanced dehumidification of supply air to an enclosed space. The refrigerant fluid circuit includes an evaporator and a reheat heat exchanger for controlling temperature and dehumidification of supply air. A variable speed fan motor controls air flow over an outdoor condenser heat exchanger whereby condenser heat exchange may be shifted progressively between the reheat heat exchanger and the condenser heat exchanger. One alternate embodiment includes a thermosiphon system for heat transfer to and from the reheat heat exchanger. Another embodiment includes a bypass air flow control damper for controlling flow of supply air through the evaporator and the reheat heat exchanger.
Claims29
A heat pump air conditioning system for controlling the temperature and humidity of supply air to an enclosed space, said system comprising:
- a refrigerant fluid circuit including a flow direction reversing valve, a compressor operable to conduct compressed refrigerant fluid vapor to a condenser heat exchanger, a reheat heat exchanger and an evaporator heat exchanger for circulating refrigerant fluid therethrough;
- a supply air blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to said enclosed space;
- a fluid expansion control device disposed in said circuit between said condenser heat exchanger and said evaporator heat exchanger;
- a first control valve disposed in said circuit between said expansion device and said condenser heat exchanger for selectively directing flow of refrigerant fluid to said evaporator heat exchanger or said reheat heat exchanger;
- a second control valve disposed in said circuit for selectively directing flow of refrigerant fluid from said reheat heat exchanger to a conduit in communication with said expansion device or from said reheat heat exchanger to a conduit extending between said evaporator heat exchanger and said reversing valve;
- temperature and humidity sensors for sensing the temperature and humidity of air in said enclosed space;
- and
- a controller operably connected to said sensors, said control valves and said reversing valve and operable for causing refrigerant fluid flow through said circuit in one operating condition of said control valves directly from said condenser heat exchanger through said evaporator heat exchanger and in another operating condition of said control valves from said condenser heat exchanger through said reheat heat exchanger and then through said evaporator heat exchanger.
5 more elements
A heat pump air conditioning system for controlling the temperature and humidity of supply air to an enclosed space, said system comprising:
- a refrigerant fluid circuit including a flow direction reversing valve, a compressor operable to conduct compressed refrigerant fluid vapor to a condenser heat exchanger, a reheat heat exchanger and an evaporator heat exchanger for circulating refrigerant fluid therethrough;
- a supply air blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to said enclosed space;
- a fluid expansion control device disposed in said circuit between said condenser heat exchanger and said evaporator heat exchanger;
- a control valve disposed in said fluid circuit between said expansion device and said condenser heat exchanger for selectively directing flow of refrigerant fluid to said evaporator heat exchanger or said reheat heat exchanger;
- a refrigerant fluid charge compensator operably connected to said circuit for storing a portion of said refrigerant fluid;
- temperature and humidity sensors for sensing the temperature and humidity of air in said enclosed space;
- and
- a controller operably connected to said sensors, said control valve and said reversing valve and operable for causing refrigerant fluid flow through said circuit in one operating condition of said control valve directly from said condenser heat exchanger through said evaporator heat exchanger and in another operating condition of said control valve from said condenser heat exchanger through said reheat heat exchanger and then through said evaporator heat exchanger.
5 more elements
An air conditioning system for conditioning supply air conducted to an enclosed space comprising:
- a refrigerant fluid circuit including a condenser heat exchanger and an evaporator heat exchanger operably connected for circulating a refrigerant fluid;
- a supply air reheat heat exchanger disposed downstream of said evaporator heat exchanger with respect to the direction of supply air flow through said evaporator heat exchanger and said reheat heat exchanger;
- a control valve for selectively controlling refrigerant fluid to flow directly from said condenser heat exchanger to said evaporator heat exchanger and from said condenser heat exchanger to said reheat heat exchanger and then to said evaporator heat exchanger;
- a blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to supply conditioned air to said space;
- a humidity sensor for sensing the humidity in said enclosed space;
- and
- a controller for controlling flow of heat exchange medium through said condenser heat exchanger whereby dehumidification of supply air flowing to said enclosed space may be controlled by the amount of heat exchange carried out by said reheat heat exchanger and said condenser heat exchanger, respectively.
4 more elements
An air conditioning system for conditioning supply air conducted to an enclosed space comprising:
- a refrigerant fluid circuit including a condenser heat exchanger and an evaporator heat exchanger operably connected for circulating a refrigerant fluid;
- a supply air reheat heat exchanger disposed downstream of said evaporator heat exchanger with respect to the direction of supply air flow through said evaporator heat exchanger and said reheat heat exchanger;
- a blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to supply conditioned air to said space;
- a humidity sensor for sensing the humidity in said enclosed space;
- a controller for controlling flow of heat exchange medium through said condenser heat exchanger whereby dehumidification of supply air flowing to said enclosed space may be controlled by the amount of heat exchange carried out by said reheat heat exchanger and said condenser heat exchanger, respectively;
- and
- a bypass conduit for bypassing refrigerant fluid in said circuit around said condenser heat exchanger when fluid flow restriction increases as reduced heat exchange takes place therein between said refrigerant fluid and said heat exchange medium.
4 more elements
An air conditioning system for conditioning supply air conducted to an enclosed space comprising:
- a refrigerant fluid circuit including a condenser heat exchanger and an evaporator heat exchanger operably connected for circulating a refrigerant fluid;
- a supply air reheat heat exchanger disposed downstream of said evaporator heat exchanger with respect to the direction of supply air flow through said evaporator heat exchanger and said reheat heat exchanger;
- a further heat exchanger disposed in said refrigerant fluid circuit between said condenser heat exchanger and said evaporator heat exchanger;
- a blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to supply conditioned air to said space;
- a humidity sensor for sensing the humidity in said enclosed space;
- said reheat heat exchanger is in circuit with said further heat exchanger for circulating a fluid therebetween to effect reheat of supply air to control humidity in said space;
- and
- a controller for controlling flow of heat exchange medium through said condenser heat exchanger whereby dehumidification of supply air flowing to said enclosed space may be controlled by the amount of heat exchange carried out by said reheat heat exchanger and said condenser heat exchanger, respectively.
5 more elements
An air conditioning system for conditioning supply air conducted to an enclosed space comprising:
- a refrigerant fluid circuit including a condenser heat exchanger and an evaporator heat exchanger operably connected for circulating a refrigerant fluid;
- a supply air reheat heat exchanger disposed downstream of said evaporator heat exchanger with respect to the direction of supply air flow through said evaporator heat exchanger and said reheat heat exchanger;
- a refrigerant fluid charge compensator operably connected to said refrigerant fluid circuit for storing a portion of said refrigerant fluid;
- a blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to supply conditioned air to said space;
- a humidity sensor for sensing the humidity in said enclosed space;
- and
- a controller for controlling flow of heat exchange medium through said condenser heat exchanger whereby dehumidification of supply air flowing to said enclosed space may be controlled by the amount of heat exchange carried out by said reheat heat exchanger and said condenser heat exchanger, respectively.
4 more elements
An air conditioning system for controlling the temperature and humidity of supply air furnished to an enclosed space, said system comprising:
- a refrigerant fluid circuit including a compressor operable to compress refrigerant fluid vapor and operable to be connected to a condenser heat exchanger, a reheat heat exchanger and an evaporator heat exchanger for circulating refrigerant fluid therethrough;
- a supply air blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to said enclosed space;
- a fan for conducting a controlled amount of ambient outdoor air over said condenser heat exchanger;
- a fan motor drivably connected to said fan for controlling the flow of air over said condenser heat exchanger;
- control valves for selectively controlling flow of refrigerant fluid through said reheat heat exchanger;
- temperature and humidity sensors for sensing the temperature and humidity of air in said enclosed space;
- a controller operably connected to said compressor and said fan for causing refrigerant fluid to flow through said condenser heat exchanger and said evaporator heat exchanger, for actuating said control valves to selectively control flow of refrigerant fluid through said reheat heat exchanger and for controlling flow of air over said condenser heat exchanger to selectively control the temperature and humidity in said enclosed space;
- and
- said compressor, said condenser heat exchanger, said fan and said fan motor comprise an outdoor portion of said system and said system may be provided by replacing an indoor portion of a prior system without replacing, adding or deleting a portion of said refrigerant fluid circuit that extends between an indoor portion of said system and said outdoor portion of said system.
6 more elements
An air conditioning system for conditioning supply air conducted to an enclosed space comprising:
- a refrigerant fluid circuit including a condenser heat exchanger and an evaporator heat exchanger operably connected for circulating a refrigerant fluid;
- a supply air reheat heat exchanger disposed downstream of said evaporator heat exchanger with respect to the direction of supply air flow through said evaporator heat exchanger and said reheat heat exchanger;
- a control valve for selectively controlling refrigerant fluid to flow directly from said condenser heat exchanger to said evaporator heat exchanger and from said condenser heat exchanger to said reheat heat exchanger and then to said evaporator heat exchanger;
- a blower for conducting supply air through said system including through said evaporator heat exchanger and then through said reheat heat exchanger to supply conditioned air to said space;
- a damper disposed downstream of said blower in the direction of flow of supply air through said system and operable for controlling the flow of at least a portion of said supply air to bypass said evaporator heat exchanger and said reheat heat exchanger;
- and
- a controller operably connected to an actuator for said damper for selectively controlling the amount of supply air to bypass said evaporator heat exchanger and said reheat heat exchanger.
4 more elements
An air conditioning system for conditioning supply air conducted to an enclosed space comprising:
- a refrigerant fluid circuit including a condenser heat exchanger and an evaporator heat exchanger operably connected for circulating a refrigerant fluid;
- a supply air reheat heat exchanger disposed downstream of said evaporator heat exchanger with respect to the direction of supply air flow through said evaporator heat exchanger and said reheat heat exchanger;
- a further heat exchanger disposed in said refrigerant fluid circuit between said condenser heat exchanger and said evaporator heat exchanger;
- a blower for conducting supply air through said evaporator heat exchanger and said reheat heat exchanger to supply conditioned air to said space;
- a humidity sensor for sensing the humidity in said enclosed space;
- said reheat heat exchanger is connected in a heat exchange fluid circuit with said further heat exchanger for circulating a heat exchange fluid therebetween to effect reheat of supply air to control humidity in said space;
- a control valve interposed in said heat exchange fluid circuit;
- and
- a controller for actuating said control valve to control the flow of said heat exchange fluid whereby dehumidification of supply air flowing to said enclosed space may be controlled by the amount of heat exchange carried out by said reheat heat exchanger and said evaporator heat exchanger, respectively.
6 more elements
Dependencies are inferred from the claim text.