Why Every DX System Is Oversized

In this video

DX systems are sized for the hottest design day, so for the vast majority of their operating hours they carry far more capacity than the load calls for. On/off and staged control can only answer part load by cycling — which drives temperature swings, high humidity, and compressor wear. Continuous modulation keeps capacity in balance with the actual load.

Key takeaways

• Equipment is sized for peak design conditions but runs at part load most of the time
• On/off and staged control meet part load by cycling, not by reducing capacity
• Cycling causes temperature swings, humidity problems, and compressor wear
• Modulating capacity keeps the system in balance with the load