For an economizer to function correctly, which two variables need to be set?

An economizer is a device used in HVAC systems to reduce energy consumption by using outdoor air to help cool a building when conditions are favorable. For an economizer to function effectively, it is crucial to monitor the outdoor dry bulb temperature and wet bulb temperature.

The outdoor dry bulb temperature indicates the current air temperature outside, which helps determine whether it is suitable to bring in outside air for cooling. The outdoor wet bulb temperature reflects the moisture content of the air and indicates the cooling potential of that air through evaporation. By comparing these two temperatures, the economizer can optimize the use of outdoor air and decide when to switch from mechanical cooling to natural ventilation.

Setting these two variables allows the economizer system to assess whether the outdoor conditions are favorable for free cooling, thereby maximizing energy efficiency and minimizing operational costs. Accurate readings and adjustments help ensure optimal performance of the HVAC system under varying weather conditions.