How much lack of cleaning can affect the fans' performances?

During the hot season, our technicians have the chance to visit many poultry houses equipped with tunnel ventilation.
Although most of the farmers plan a good routine maintenance and clean their barns, many others don’t understand the importance of keeping their fans in optimal conditions.

One of the main steps is the cleaning of safety netting and guard on drive belt. According to with many studies, in presence of dust deposit, the fan performance can be cut-off by even 30%.
In other words, if a fan can normally reach 40.000 m3/h, it can only reach 28.000 m3/h when not properly clean.
These results can also affect the wind-chill effect, cutting its benefits up to 50%: from 8°C to 4.5°C of cooling effect. Those numbers are absolutely realistic and without a proper cleaning also the optimum bird growth rates can be affected by negative results also in the final output.
What to do?

Clean the fans on a monthly basis. Just a simple dusting-off with a softer bristle broom could be the right trick. Be sure to clean fans deeply at least once a flock.

In conclusion, the only way to get the best output is to keep the equipment in top shape. According to a research of Mississippi University, a reduction of 30% in air speed inside the barn results in a loss in birds body weight around 6%, worsening in the feed conversion factor and increasing in the mortality rate.

Are you able to estimate how much the lack of cleaning affect your profit?