Low ambient outdoor coil restrictor plate for air conditioner

Abstract

A low ambient cooling system for a variable refrigerant flow heat pump includes an outdoor air conditioning unit and an indoor air conditioning unit. The outdoor air conditioning unit includes an outdoor heat exchanger with one or more valves that selectively control refrigerant flow through different sections of condenser coils during a low ambient cooling mode. During the low ambient cooling mode, the condenser coils of the outdoor heat exchanger include an active coil section through which refrigerant flows and an inactive coil section that is closed. An outdoor-coil restrictor plate with holes is attached to the active condenser coil in the outdoor air conditioning unit. The outdoor-coil restrictor plate restricts excessive heat release from the active coil section of the condenser coils in the outdoor heat exchanger during the low ambient cooling mode.

What is claimed: 
     
         1 . A low ambient cooling system for a variable refrigerant flow heat pump, comprising:
 an outdoor air conditioning unit that includes a compressor, a fan, and a housing that includes an air inlet and an air outlet;   an outdoor heat exchanger that is installed in the housing of the outdoor air conditioning unit and that includes one or more valves configured to selectively control refrigerant flow through different sections of condenser coils during a low ambient cooling mode, the condenser coils of the outdoor heat exchanger include an active coil section through which refrigerant flows during the low ambient cooling mode and inactive coil section that is closed during the low ambient cooling mode; and   an active-outdoor-coil restrictor plate that includes an inner surface attached to the active coil section, an outer surface opposite to the inner surface, an edge that connects the outer surface to the inner surface, and holes that extend from the outer surface to the inner surface to reduce excessive heat release from the active coil section of the condenser coils in the outdoor heat exchanger during the low ambient cooling mode.   
     
     
         2 . The low ambient cooling system according to  claim 1 , further comprising
 an indoor air conditioning unit that includes an evaporator in the low ambient cooling mode and that is connected to the outdoor air conditioning unit through piping and an expansion valve.   
     
     
         3 . The low ambient cooling system according to  claim 1 , further comprising a wind guard attached to the housing of the outdoor air conditioning unit. 
     
     
         4 . The low ambient cooling system according to  claim 1 , further comprising
 a controller configured to control the valves of the of the outdoor heat exchanger to selectively control refrigerant flow through the active coil section and the inactive coil section of the outdoor heat exchanger during the low ambient cooling mode.   
     
     
         5 . The low ambient cooling system according to  claim 4 , wherein
 the controller is configured to control the valves to open refrigerant flow through the active coil section of the outdoor heat exchanger and to open refrigerant flow through the inactive coil section of the outdoor heat exchanger during a high ambient cooling mode.   
     
     
         6 . The low ambient cooling system according to  claim 1 , wherein
 the active-outdoor-coil restrictor plate is reversibly fastenable to the active coil section of the outdoor heat exchanger.   
     
     
         7 . The low ambient cooling system according to  claim 1 , wherein
 the holes of the active-outdoor-coil restrictor plate are circular or rectangular.   
     
     
         8 . The low ambient cooling system according to  claim 1 , wherein
 the active-outdoor-coil restrictor plate includes one or more rows of the holes.   
     
     
         9 . The low ambient cooling system according to  claim 8 , wherein
 the active-outdoor-coil restrictor plate includes one or more columns of the holes.   
     
     
         10 . The low ambient cooling system according to  claim 1 , wherein the active-outdoor-coil restrictor plate includes one or more columns of the holes. 
     
     
         11 . The low ambient cooling system according to  claim 1 , wherein
 the holes of the active-outdoor-coil restrictor plate are uncovered.   
     
     
         12 . The low ambient cooling system according to  claim 1 , wherein
 the holes in the active-outdoor-coil restrictor plate are cutouts.   
     
     
         13 . A method of restricting heat release in an outdoor heat exchanger during low ambient cooling, comprising:
 providing an outdoor unit configured to perform a low ambient cooling mode, the outdoor unit includes condenser coils having an active coil section and an inactive coil section in the low ambient cooling mode;   attaching an inner surface of an active-outdoor-coil restrictor plate to the active coil section of the condenser coils of the outdoor unit, the active-outdoor-coil restrictor plate includes holes; and   restricting, via the active-outdoor-coil restrictor plate, heat release in the active coil section of the outdoor unit during the low ambient coiling mode.   
     
     
         14 . The method according to  claim 13 , further comprising
 detecting an outdoor ambient temperature,   determining whether the outdoor ambient temperature is at, or below, a predetermined temperature; and   controlling the outdoor unit to perform the low ambient cooling mode in response to determining that the predetermined temperature is at, or below, the predetermined temperature.   
     
     
         15 . The method according to  claim 13 , wherein
 the holes of the active-outdoor-coil restrictor plate are uncovered.