Method and apparatus for removing ice from outdoor housing for an environmental conditioning unit

Abstract

A method for removing ice from an outdoor housing for an environmental conditioning unit that includes the housing surrounding a coil and a fan for moving air past the coil includes the steps of: (a) operating the fan at a first speed in a first direction to move air in a first flow past the coil while the conditioning unit is in a heating mode; (b) disengaging the fan when the conditioning unit is in a defrost mode; (c) operating the fan at a second speed in a second direction to move air in a second flow past the coil when an operational parameter attains a first value; and (d) operating the fan in the first direction at the first speed to move air in the first flow when the operational parameter attains a second value.

1 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit; said environmental conditioning unit including a coil structure and a fan configured for moving air past said coil structure; said housing substantially surrounding said coil; the method comprising the steps of:
 (a) operating said fan at a first speed in a first direction to move air in a first flow past said coil structure while said environmental conditioning unit is in a heating operational mode;   (b) disengaging said fan for at least a portion of a time when said environmental conditioning unit is in a defrost operation mode;   (c) operating said fan at a second speed in a second direction to move air in a second flow past said coil structure when at least one selected operational parameter substantially attains a selected first predetermined value; and   (d) operating said fan in said first direction at said first speed to move air in said first flow when said at least one selected operational parameter substantially attains a selected second predetermined value.   
   
   
       2 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 1  wherein said coil flowingly contains a fluid and wherein said at least one operational parameter is temperature of said fluid as said fluid exits said coil. 
   
   
       3 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 1  wherein said first speed and said second speed are substantially equal. 
   
   
       4 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 1  wherein said at least one first predetermined value said at least one second predetermined value are selected appropriately to assure that said environmental conditioning unit is in said defrost operation mode when said at least one first predetermined value said at least one second predetermined value are attained. 
   
   
       5 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 2  wherein said first speed and said second speed are substantially equal. 
   
   
       6 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 2  wherein said at least one first predetermined value said at least one second predetermined value are selected appropriately to assure that said environmental conditioning unit is in said defrost operation mode when said at least one first predetermined value said at least one second predetermined value are attained. 
   
   
       7 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 3  wherein said at least one first predetermined value said at least one second predetermined value are selected appropriately to assure that said environmental conditioning unit is in said defrost operation mode when said at least one first predetermined value said at least one second predetermined value are attained. 
   
   
       8 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 5  wherein said at least one first predetermined value said at least one second predetermined value are selected appropriately to assure that said environmental conditioning unit is in said defrost operation mode when said at least one first predetermined value said at least one second predetermined value are attained. 
   
   
       9 . A method for effecting ice removal from an outdoor housing for a heat pump environmental conditioning unit; said heat pump unit including a coil structure, a reversing valve and a fan configured for moving air past said coil structure; said housing substantially surrounding said coil; said heat pump unit operating in a heating mode when said reversing valve unit is in a first orientation; said heat pump unit operating in a cooling mode when said reversing valve is in a second orientation; the method comprising the steps of:
 (a) operating said fan at a first speed in a first direction to move air in a first flow about said coil structure while said heat pump unit is in said heating mode;   (b) disengaging said fan and orienting said reversing valve in said second orientation when said heat pump unit substantially attains a predetermined first operating condition to place said heat pump unit in a defrost mode;   (c) operating said fan at a second speed in a second direction to move air in a second flow past said coil structure when said heat pump unit is in said defrost mode and said heat pump unit substantially attains a predetermined second operating condition; and   (d) engaging said fan and orienting said reversing valve in said first orientation when said heat pump unit substantially attains a predetermined third operating condition to place said heat pump unit in said heating mode.   
   
   
       10 . A method for effecting ice removal from an outdoor housing for a heat pump environmental conditioning unit as recited in  claim 9  wherein said coil flowingly contains a fluid between a first coil end and a second coil end, and wherein at least one of said first operating condition, said second operating condition and said third operating condition is related to temperature of said fluid substantially adjacent one of said first coil end and said second coil end. 
   
   
       11 . A method for effecting ice removal from an outdoor housing for a heat pump environmental conditioning unit as recited in  claim 9  wherein said first speed and said second speed are substantially equal. 
   
   
       12 . A method for effecting ice removal from an outdoor housing for a heat pump environmental conditioning unit as recited in  claim 1  wherein said first operating condition and said second operating condition are selected appropriately to assure that said heat pump unit is in said defrost mode when said second operating condition is attained. 
   
   
       13 . A method for effecting ice removal from an outdoor housing for a heat pump environmental conditioning unit as recited in  claim 10  wherein said first speed and said second speed are substantially equal. 
   
   
       14 . A method for effecting ice removal from an outdoor housing for a heat pump environmental conditioning unit as recited in  claim 10  wherein said first operating condition and said second operating condition are selected appropriately to assure that said heat pump unit is in said defrost mode when said second operating condition is attained. 
   
   
       15 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 11  wherein said first operating condition and said second operating condition are selected appropriately to assure that said heat pump unit is in said defrost mode when said second operating condition is attained. 
   
   
       16 . A method for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 13  wherein said first operating condition and said second operating condition are selected appropriately to assure that said heat pump unit is in said defrost mode when said second operating condition is attained. 
   
   
       17 . An apparatus for effecting ice removal from an outdoor housing for an environmental conditioning unit; said environmental conditioning unit including a coil structure, a reversing valve and a fan configured for moving air past said coil structure; said environmental conditioning unit operating in a heating mode when said reversing valve unit is in a first orientation; said environmental conditioning unit operating in a cooling mode when said reversing valve is in a second orientation; said housing substantially surrounding said coil; the apparatus comprising:
 (a) a control unit coupled with said fan;   (b) at least one sensor unit coupled with said control unit and coupled with said coil structure for sensing at least one predetermined operating parameter associated with said fluid;   (c) said control unit cooperating with said at least one sensor unit to effect operating said fan at a first speed in a first direction to move air in a first flow past said coil structure while said environmental conditioning unit is in said heating mode;   (e) said control unit cooperating with said at least one sensor unit to effect disengaging said fan and orienting said reversing valve in said second orientation when said environmental conditioning unit substantially attains a predetermined first operating condition to place said environmental conditioning unit in a defrost mode;   (f) said control unit cooperating with said at least one sensor unit to effect operating said fan at a second speed in a second direction to move air in a second flow past said coil structure when said environmental conditioning unit is in said defrost mode and said environmental conditioning unit substantially attains a predetermined second operating condition; and   (g) said control unit cooperating with said at least one sensor unit to effect operating said fan in said first direction at said first speed to move air in said first flow when said environmental conditioning unit substantially attains a predetermined third operating condition.   
   
   
       18 . An apparatus for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 17  wherein said coil flowingly contains a fluid between a first coil end and a second coil end, and wherein at least one of said first operating condition, said second operating condition and said third operating condition is related to temperature of said fluid substantially adjacent one of said first coil end and said second coil end. 
   
   
       19 . An apparatus for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 17  wherein said first speed and said second speed are substantially equal. 
   
   
       20 . An apparatus for effecting ice removal from an outdoor housing for an environmental conditioning unit as recited in  claim 19  wherein said first operating condition and said second operating condition are selected appropriately to assure that said heat pump unit is in said defrost mode when said second operating condition is attained.