US 9,810,469 B2
Variable fan speed control in HVAC systems and methods
Michael Carl Boehde, Onalaska, WI (US)
Assigned to TRANE INTERNATIONAL INC., Davidson, NC (US)
Filed by TRANE INTERNATIONAL INC., Piscataway, NJ (US)
Filed on Oct. 10, 2013, as Appl. No. 14/50,785.
Claims priority of provisional application 61/711,938, filed on Oct. 10, 2012.
Prior Publication US 2014/0096547 A1, Apr. 10, 2014
Int. Cl. F25D 17/00 (2006.01); F25B 39/04 (2006.01); F25B 41/00 (2006.01); F25B 49/02 (2006.01); F04D 27/00 (2006.01); F24F 1/06 (2011.01); F24F 1/50 (2011.01); F24F 11/00 (2006.01); F04D 27/02 (2006.01)
CPC F25B 49/027 (2013.01) [F04D 27/004 (2013.01); F04D 27/0261 (2013.01); F24F 1/06 (2013.01); F24F 1/50 (2013.01); F24F 11/0079 (2013.01); F25B 2700/2106 (2013.01); Y02B 30/746 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A method of controlling condenser fans in a heating, ventilation, and air conditioning (HVAC) system, comprising:
detecting, with a device to detect ambient air temperature, ambient air temperature;
obtaining, with a device to obtain compressor present load, a present load on a variable speed compressor;
determining, with a controller, a target differential pressure between a condenser and an evaporator based on the ambient air temperature detected and the present load on the variable speed compressor obtained;
outputting, with the controller, a condenser fan speed suitable to achieve the target differential pressure determined; and
controlling one or more fans based on the output of condenser fan speed to obtain a fan capacity suitable to control one or more condenser fans, such that power of the HVAC system is managed through a power consumed by the variable speed compressor and the fans.