Micro Chiller-Based Heating, Ventilation, and Air Conditioning System

Abstract

A heating, ventilation, and air conditioning system in which a primary water loop is used as a heat transfer reservoir for both heating and cooling. A plurality of micro chillers are provided, with each micro chiller being connected to the primary water loop. Each micro chiller includes its own heat engine. Each micro chiller includes one or more fan coil units that exchange heat between the micro chiller and the air in a building. In a first mode a micro chiller transfers heat from the air in the building to the water circulating within the primary water loop. In a second mode the micro chiller transfers heat from the water circulating in the primary water loop to the air in the building. A primary water loop regulation system is provided to control the temperature of the water circulating in the primary water loop.

Having described my invention, I claim: 
     
         1 . A method for controlling a temperature in a first space and a second space within a building, comprising:
 (a) providing a first fan unit having a first liquid coil and a first fan, with said first fan configured to blow air over said first liquid coil and into said first space;   (b) providing a second fan unit having a second liquid coil and a second fan, said second fan configured to blow air over said second liquid coil and into said second space;   (c) providing a first micro chiller including,
 (i) a first compressor, 
 (ii) a first condenser, 
 (iii) a first expansion valve, 
 (iv) a first evaporator, and 
 (v) a first refrigerant circulation loop configured to circulate said refrigerant from said first compressor to said first condenser, to said first expansion valve, to said first evaporator, and back to said first compressor; 
   (d) providing a second micro chiller including,
 (i) a second compressor, 
 (ii) a second condenser, 
 (iii) a second expansion valve, 
 (iv) a second evaporator, and 
 (v) a second refrigerant circulation loop configured to circulate said refrigerant from said second compressor to said second condenser, to said second expansion valve, to said second evaporator, and back to said second compressor; 
   (e) providing a primary liquid loop running through said building;   (f) providing a first secondary liquid loop running between said first microchiller and said first fan unit;   (g) providing a second secondary liquid loop running between said second microchiller and said second fan unit;   (h) providing a first set of valves controlling flow through said first evaporator of said first micro chiller;   (i) providing a second set of valves controlling flow through said first condenser of said first micro chiller;   (j) providing a third set of valves controlling flow through said second evaporator of said second micro chiller;   (k) providing a fourth set of valves controlling flow through said second condenser of said second micro chiller;   (l) heating said first space by setting said first set of valves to circulate liquid from said primary liquid loop through said first evaporator and setting said second set of valves to circulate liquid from said first secondary liquid loop through said first condenser; and   (m) cooling said second space by setting said third set of valves to circulate liquid from said second secondary liquid loop through said second evaporator and setting said fourth set of valves to circulate liquid from said primary liquid loop through said second condenser.   
     
     
         2 . The method for controlling a temperature in a space within a building as recited in  claim 1 , comprising maintaining said primary liquid loop between 15 degrees centigrade and 30 degrees centigrade. 
     
     
         3 . The method for controlling a temperature in a space within a building as recited in  claim 1 , wherein said primary liquid loop and said secondary liquid loop contain water. 
     
     
         4 . The method for controlling a temperature in a space within a building as recited in  claim 1 , wherein said primary liquid loop is connected directly to a geothermal loop, so that liquid passing through said primary liquid loop also passes through said geothermal loop. 
     
     
         5 . The method for controlling a temperature in a space within a building as recited in  claim 1 , wherein said primary liquid loop is connected to a geothermal loop by a geothermal heat pump. 
     
     
         6 . The method for controlling a temperature in a space within a building as recited in  claim 5 , comprising:
 (a) wherein said geothermal heat pump includes an evaporator and a condenser;   (b) providing an evaporator valve set configured to selectively connect said primary water loop and said geothermal loop to said evaporator; and   (c) providing a condenser valve set configured to selectively connect said primary water loop and said geothermal loop to said condenser.   
     
     
         7 . The method for controlling a temperature in a space within a building as recited in  claim 5 , comprising:
 (a) wherein said geothermal heat pump includes an evaporator and a condenser;   (b) wherein said geothermal heat pump includes a reversing valve for selectively reversing a flow of refrigerant in said geothermal heat pump;   (c) providing a connection between said primary water loop and said condenser; and   (d) providing a connection between said geothermal loop and said evaporator.