Start-Up of Air Conditioning Systems After Periods of Shutdown (Humidity Considerations)

Abstract

In many cases the single most important energy conservation measure that can be taken is to turn equipment off when it is not needed. In the case of air conditioning, this generally means turning it off when occupants leave and turning it back on in time to have the space comfortable when they return. In humid climates special problems are often encountered when a system is restarted after a period of shutdown. The temperature and humidity in the space rises during the period of shutdown. Unfortunately the latent load required to bring the space back to comfort conditions is usually much higher than the sensible load. Most methods of control are ill suited for this duty. This paper examines the response of various types of air conditioning systems during this recovery period and makes recommendations for system designers.