AHU's & PLANT ROOMS
The condition of the AHU needs to be monitored conscientiously not only for reasons of microbial control but also to minimise energy usage and to improve plant reliability.
Cooling Coils incorporated in an AHU will accumulate organic dust with neglect or poor air-filtration. The water running over its surface may collect microbial matter before being blown directly into the air path if the air velocity over all or part of the coil is excessive.
Most AHU systems don't operate efficiently because of dirt and dust. A build-up of 0.1cm of dirt on a heating or cooling coil can result in a 21% decrease in efficiency!