Commercial buildings consume a significant portion of their energy on heating, ventilation, and air conditioning (HVAC) systems — and Direct Expansion (DX) coils play a major role in that energy demand. Fortunately, with the right strategies, DX coil-based systems can be optimized to reduce electricity consumption without sacrificing indoor comfort.
Below are effective, field-proven energy-saving tips tailored specifically for commercial buildings using DX coils in their HVAC systems.
Schedule Regular Coil Cleaning
Dust, mold, and grime buildup on DX coils can drastically reduce heat transfer efficiency, forcing compressors to work harder and run longer.
Optimize Refrigerant Charge and Superheat Settings
Improper refrigerant levels — either undercharged or overcharged — reduce cooling efficiency. Undercharged systems can cause coil icing, while overcharged systems result in high head pressure.
Use Programmable Thermostats with Setback Features
In office spaces, conference rooms, or retail stores, smart thermostats can significantly reduce cooling during unoccupied hours.
Zone Cooling for Targeted Air Conditioning
Instead of cooling the entire floor, use zoned DX systems to provide cooling only where needed. This is especially beneficial in buildings with uneven occupancy or usage.
Ensure Proper Coil Sizing
Oversized or undersized DX coils lead to inefficiencies. Oversizing causes short cycling and humidity issues, while undersizing forces continuous compressor operation.
Incorporate Variable Speed Drives (VFDs)
Pairing DX coils with VFD-controlled fans or blowers helps modulate airflow according to cooling demand. This avoids over-ventilation and unnecessary fan energy use.