Introduction: In 2001 a climate control system was installed to serve the basement research laboratories and shop of Bennett Hall to provide ventilation air amounts to meet current OSHA standards of 6 air changes per hour for laboratories where chemicals are used, and a comfortable working environment year around. The system provides the ventilation air and keeps the environment at a comfortable temperature, but does not provide low enough humidity on days with high dew points of outside air.

Goal: Redesign the system to provide good humidity control at less  the 50% with comfortable working temperatures. This humidity level will allow Professor Hess and Smith to perform their experiments with less ice build up on their test apparatuses as well as reduce the amount of rust build up on machines in the Machine Shop.  

Background: The figure below shows a schematic of the existing system. Ventilation air for the entire basement is brought in and cooled (or heated depending on the season) in a central air handler, and is then sent to the individual room unit coolers which mix re-circulated room air with the ventilation air and provide additional cooling in summer if needed. The problem with the system is that it does not remove enough water vapor from the ventilation air in summer to always keep the humidity low enough. The humidity is high enough sometimes, for rust to form on some equipment in the Machine Shop and for ice to form on test ridges in both Professor Hess and Smith's Laboratories. After meeting with both Professors and the Machine Shop Supervisor, a humidity level of  50 % was desired by all parties. This desired humidity level will prevent condensation on cryogenic equipment or electrical leakage from very high voltage sources and will reduce the amount of rust accumulation on the machines in the Shop.