One of the simplest ways to get free cooling is by including an economizer on your rooftop unit.
Adding an economizer to your rooftop unit can save you between 14-40% each year on your energy bill.
An economizer is a damper, or adjustable opening, that is controlled by a sensor which measures one or more of three things:
- Outside air temperature,
- Outside air humidity, and/or
- CO2 levels of inside air (for air quality purposes).
The sensor compares the temperature and humidity of the outside air to the return air from inside the building and then sends whichever air is “more efficient” to the unit. The drier and cooler the air is, the less energy is needed to condition it.
When the outside air hits low enough temps, the AC compressor doesn’t need to run at all, hence, free cooling!