HVAC System and Method Using Exhaust Driven Air Transfer

Abstract

A method for conditioning a building includes drawing unconditioned outside air at a first flow rate through a dedicated outdoor air system unit, conditioning the outside air by the dedicated outdoor air system unit to conditioned air, supplying the conditioned air to a first room, and exhausting the conditioned air at a second flow rate to an exterior of the building by a kitchen exhaust fan located in a second room. The first and second rooms can be in fluid communication with a common area of the building such that the conditioned air from the first room is drawn to the second room via the common area to supply conditioned air to the common area and second room. The second flow rate can be controlled by a temperature sensor adjacent the kitchen exhaust fan.

1 . A method for air conditioning a building, the method comprising:
 drawing unconditioned outside air at a first flow rate through a dedicated outdoor air system unit;   conditioning the unconditioned outside air by the dedicated outdoor air system unit to conditioned air;   supplying the conditioned air to a first room of the building, and   exhausting the conditioned air at a second flow rate to an exterior of the building by a kitchen exhaust fan located in a second room of the building, the first and second rooms being in fluid communication with a common area of the building such that the conditioned air from the first room is drawn to the second room via the common area to supply conditioned air to the common area and the second room, the second flow rate being controlled by a sensor adjacent the kitchen exhaust fan,   wherein, the first flow rate is equal to or greater than the second flow rate, the first flow rate being set based on the second flow rate.   
     
     
         2 . The method of  claim 1 , wherein the dedicated outdoor air system unit is the sole outdoor air supply for conditioning air to the building. 
     
     
         3 . The method of  claim 1 , wherein the exhausting step includes activating the kitchen exhaust fan when a first temperature sensed under a hood of the kitchen exhaust fan in the second room is greater than a second temperature at a different location. 
     
     
         4 . The method of  claim 1 , wherein the common area is a hallway connecting the first and second rooms. 
     
     
         5 . The method of  claim 1 , wherein the exhausting step includes allowing the conditioned air to pass from the common area into the second room without ductwork. 
     
     
         6 . The method of  claim 1 , further comprising allowing the conditioned air to pass from the first room and common area into the second room without ductwork when a pressure difference exists between the first room, common area, and second room. 
     
     
         7 . The method of  claim 1 , further comprising recirculating and reconditioning previously conditioned air from the common area to the dedicated outdoor air unit and supplying newly conditioned air to the first room and the common area. 
     
     
         8 . The method of  claim 1 , further comprising supplying conditioned air from the dedicated outdoor air system unit to a third room of the building in fluid communication with any of the first room, second room and common area. 
     
     
         9 . The method of  claim 1 , further comprising modulating the second flow rate based on a temperature sensed by the temperature sensor and increasing the first flow rate proportionally with the second flow rate as the second flow rate increases. 
     
     
         10 . The method of  claim 1 , wherein the supplying step includes supplying the conditioned air at a constant flow rate. 
     
     
         11 . The method of  claim 1 , wherein the sensor is at least one of a temperature sensor and an optical sensor. 
     
     
         12 . The method of  claim 11 , wherein the second flow rate is controlled by a smoke level detected by the optical sensor. 
     
     
         13 . A system for air conditioning a building comprising:
 a kitchen exhaust fan located in a kitchen of the building, the kitchen exhaust fan configured to exhaust conditioned air from the kitchen;   a first temperature sensor located adjacent the kitchen exhaust fan for controlling the kitchen exhaust fan;   a building management system; and   a dedicated outdoor air system unit configured to draw in unconditioned outside air, condition the unconditioned outside air, and supply conditioned air to a common area in fluid communication with the kitchen.   
     
     
         14 . The system of  claim 13 , further comprising a second temperature sensor located away from the kitchen exhaust fan. 
     
     
         15 . The system of  claim 13 , wherein the building management system is in communication with the first and second temperature sensors. 
     
     
         16 . The system of  claim 15 , wherein the dedicated outdoor air system unit is in communication with the building management system. 
     
     
         17 . The system of  claim 13 , further comprising an outdoor air damper positioned within an exterior wall of the dedicated outdoor air system unit. 
     
     
         18 . The system of  claim 17 , wherein the dedicated outdoor air system unit opens the outdoor air damper to draw in the unconditioned outside air. 
     
     
         19 . The system of  claim 17 , wherein the dedicated outdoor air unit closes the outdoor air damper when a recirculation setting is initiated such that outside air is not drawn into the dedicated outdoor air unit. 
     
     
         20 . The system of  claim 17 , wherein the dedicated outdoor air unit includes a recirculation air damper, and is configured to close the outdoor air damper such that outside air is not drawn into the dedicated outdoor air unit and opens the recirculation air damper such that the air from within the building is drawn into the dedicated outdoor air unit.