Indoor Air Pressure Management

Abstract

A strategy for minimizing or avoiding the so-called stack effect within buildings ( 20 ) includes controlling the temperature within a vertically extending shaft ( 40 ) such as an elevator hoistway or stairwell. Controlling the air pressure at each of a plurality of levels (A, B, C, D) within the useable or occupied space of a building ( 20 ) allows for controlling a pressure differential between the useable or occupied space and an interior of the shaft ( 40 ). Maintaining appropriate pressure differential levels allows for minimizing or avoiding the stack effect that otherwise results in undesirably large drafts between the building interior and the outside, surrounding environment.

1 . An elevator hoistway, comprising:
 a shaft through which an elevator cab can move; and   a temperature control mechanism associated with, the shaft to control a temperature within the shaft such that the temperature in the shaft corresponds to an outdoor temperature near the shaft, the temperature control mechanism directing airflow within the shaft in a first direction when the outdoor temperature is lower than, the temperature in the shaft and directing airflow within the shaft in a second, opposite direction when the outdoor temperature is higher than the temperature in the shaft.   
   
   
       2 . The elevator hoistway of  claim 1 , wherein the temperature control mechanism comprises at least one opening near each of opposite ends of the shaft, each of the openings permitting airflow between the shaft and an outdoor environment near the shaft. 
   
   
       3 . The elevator hoistway of  claim 2 , including at least, one temperature sensor that provides an indication of the temperature in at least a portion of the shaft. 
   
   
       4 . The elevator hoistway of  claim 3 , including an sir mover that selectively varies an amount of airflow between the shaft and the outdoor environment responsive to an indication from the temperature sensor that the temperature in the shaft does not correspond to the outdoor temperature within a selected range, 
   
   
       5 . The elevator hoistway of  claim 2 , wherein the openings establish an airflow passage through the shaft for outdoor air to flow through the shaft 
   
   
       6 . The elevator hoistway of  claim 1 , wherein the temperature control mechanism maintains the temperature in the shaft approximately equal to the outdoor temperature. 
   
   
       7 . A method of controlling airflow through a generally vertical shaft in a building having a plurality levels, comprising the steps of:
 adjusting a temperature in the shaft to correspond to an outdoor temperature outside of the building; and   controlling an air pressure of at least one level of the building based upon the temperature in the shaft.   
   
   
       8 . The method of  claim 7 , including adjusting the air pressure of the at least one level to maintain a pressure difference between the shaft and the level within a selected range. 
   
   
       9 . The method of  claim 7 , including controlling the air pressure of each of the plurality of levels individually. 
   
   
       10 . The method of  claim 7 , including grouping at least two of the plurality of levels in a zone and controlling the air pressure of the zone, 
   
   
       11 . The method of  claim 7 , including controlling the air pressure of each of the plurality of levels to achieve a desired pressure differential between the shaft and each level. 
   
   
       12 . The method of  claim 7 , including increasing an amount of airflow on at least one of the levels to increase the pressure on the at least one level. 
   
   
       13 . The method of  claim 7 , wherein the shaft comprises one of a stairwell, or an elevator hoistway, 
   
   
       14 . The method of  claim 7 , including directing airflow in the shaft in a first direction when the outdoor temperature is lower than the temperature in the shaft and in a second, opposite direction when the outdoor temperature is higher than the temperature in the shaft. 
   
   
       15 . The method of  claim 7 , wherein the building includes a plurality of generally vertical shafts and the method includes coordinating the temperatures within the shafts. 
   
   
       16 . A building comprising:
 a plurality of levels;   at least one elevator hoistway shaft that provides access to at least some of the plurality of levels;   at least one stairwell shaft that provides access to at least some of the plurality of levels; and   a temperature, control mechanism associated with each of the shafts to control a temperature within each shaft such that the temperatures in the shafts are coordinated and correspond to an outdoor temperature outside of the building,   
   
   
       17 . The building of  claim 16 , comprising a pressure control device that controls an air pressure on each of the at least some of the plurality of levels. 
   
   
       18 . The building of  claim 17 , wherein the pressure control device maintains the air pressure on each level to achieve a desired pressure differential between the air pressure on the level and an air pressure in at least the elevator hoistway shaft 
   
   
       19 . The building of  claim 16 , wherein the temperature control mechanism directs airflow within at least the elevator hoistway shaft in a first direction when the outdoor temperature is lower than the temperature in the elevator hoistway shaft and in a second opposite direction when the outdoor temperature is higher than the temperature hi the elevator hoistway shaft. 
   
   
       20 . The building of  claim 19 , wherein the temperature control mechanism also directs airflow within the stairwell shaft in the first and second directions.