The thermostat will tell the PEARL to enable the supply fan and open the outside damper to increase the ventilation rate. This increased ventilation rate is a ratio of starting at the Minimum Damper Position at the thermostat’s CO2 Ventilation configuration and being at 100% open if the room’s CO2 levels reach 1500 PPM. But, the PEARL will never increase the ventilation rate beyond its configured Maximum Ventilation Position.
Any time the CO2 levels are below the configured CO2 Ventilation setting, the thermostat will tell the PEARL to set the outside damper at the Minimum Damper Position anytime a heating, cooling, or fan cycle is running.