Fan Assemblies, Mechanical Draft systems and Methods

Abstract

Fan assemblies, mechanical draft systems and methods are provided. In this regard, a representative mechanical draft system for use with multiple appliances includes: a chimney operative to direct combustion products from multiple appliances; a chimney fan operative to draw combustion products from the chimney; and a controller operative to adjust an operating speed of the chimney fan such that, responsive to a change in pressure in the chimney, the controller adjusts the operating speed of the chimney fan to maintain a desired pressure in the chimney.

1 - 20 . (canceled) 
     
     
         21 . An exhaust fan assembly comprising:
 a housing defining a chamber and having opposing openings, the opposing openings having a centerline extending therebetween, a first of the openings being operative to intake a flow of gases, a second of the openings being operative to exhaust the flow of gases from the chamber; and   a centrifugal fan having a motor and an impeller, the motor being mounted external to the housing, the impeller being positioned within the chamber, a rotational axis of the impeller being inclined with respect to the centerline extending between the openings of the housing.   
     
     
         22 . The assembly of  claim 21 , further comprising:
 an inlet operative to provide the flow of gases to the first of the openings; and   a outlet operative to receive the flow of gases from the second of the openings;   the inlet, the openings of the housing and the outlet being arranged in an in-line configuration.   
     
     
         23 . The assembly of  claim 21 , wherein the rotational axis of the impeller intersects the centerline. 
     
     
         24 . The assembly of  claim 21 , further comprising a cooling plate positioned between the motor and the exterior of the housing. 
     
     
         25 . The assembly of  claim 21 , wherein the assembly further comprises a divider positioned within the housing and being operative to partition the chamber into an intake compartment, communicating with the first of the openings, and an exhaust compartment, communicating with the second of the openings, the partition being further operative to restrict gases from the intake chamber from leaving the housing without flowing through the impeller. 
     
     
         26 . The assembly of  claim 25 , wherein the divider is inclined with respect to the centerline.