How much energy savings can I expect from an RTU retrofit?

Energy savings depend on which controls are installed. Programmable thermostats alone can save up to 15% with setbacks, or over 30% when also shutting down fans during unoccupied periods. Economizers provide payback within one to two years depending on climate and usage. VFDs provide exponential savings—reducing fan speed by 10% can reduce fan energy use by 27%, and reducing by 33% can reduce usage by 69%. Honeywell provides free savings estimator tools at their website to calculate specific savings for your conditions.