HOUSING
PIH-41
pork industry handbook
COOPERATIVE EXTENSION SERVICE • PURDUE UNIVERSITY • WEST LAFAYETTE, INDIANA
Maintenance and Operation of Ventilation Fans for Hog Barns
Authors
Dexter Johnson, North Dakota State University
Marvin Hall, University of Illinois
Reviewers
Raymond C. Benz, University of Arkansas
Robert C. McDaniel, University of Arkansas
Ventilation Equipment
The purpose of this fact sheet is to assist in obtaining good performance from a hog barn ventilation system. Consult the fan manufacturer’s literature for recommendations when possible. Designing the hog barn ventilation system is explained in other Pork Industry Handbook fact sheets or MWPS-8, Midwest Plan Service, Iowa State University, Ames, Iowa.

Frequently, the ventilation system is blamed for poor performance when actually it was not installed correctly or is not properly operated and maintained. A properly designed and operated fan ventilation system will keep a building reasonably dry and odor levels tolerable in cold weather. At near zero and lower temperatures, supplemental heat will be needed for farrowing barns, nursery barns and grower barns not filled to capacity, because animals cannot warm the necessary fresh ventilation air and also keep the building warm. In hot weather, a ventilation system (along with sprinklers or air coolers) can reduce temperatures and high humidity buildup. Use information from Table 1 and Figure 9 to check equipment capability.

A combination of (1) a small fan and large fans or (2) a small fan and 2-speed fans or (3) variable-speed fans is required to provide the range of air movement capacities needed for the various ventilation conditions in the barn throughout the year. Too large a continuous-operating fan wastes heat and causes drafts. To avoid cold drafts on hogs, install exhaust fans in the wall away from prevailing wind and near the ceiling. Use extra fans inside the barn to circulate the air during hot weather.

Select fans according to their capacity at 1/8 in. static pressure (water gauge) to assure desired air-movement operation of the several fans in the system. Pit fans and other small fans need good operating characteristics to prevent large fans from "outpulling” them and causing air to go backward through the fan. Well-built fans have smooth edges and few corners to catch dirt. Keep in mind
Cooperative Extension Work in Agriculture and Home Economics State of Indiana. Purdue University and U. S. Department of Agriculture Cooperating. H. G. Diesslin, Director, West Lafayette, Ind. Issued in furtherance of the Acts of May 8 and June 30, 1914. It is the policy of the Cooperative Extension Service of Purdue University that all persons shall have equal opportunity and access to its programs and facilities without regard to race, religion, color, sex or national origin