Mixed air in HVAC systems is the blend of return air from the building and outdoor air. Conventional control strategies waste significant energy by continuously maintaining the mixed air at a temperature cold enough to satisfy the building’s maximum cooling requirement. During most operating conditions this results in unnecessary overcooling, forcing the heating system to reheat the air to maintain comfort—a costly cycle of simultaneous cooling and heating.
DX Cooling Opportunity
HVAC systems that mix fresh air and building return air to varying quantities for cooling purposes often have control logic comparing the total heat content of the outdoor to the total heat content of the return air.