Defrost control strategies, such as time-temperature defrost, pressure-based defrost, and demand-defrost, manage the defrost cycle to ensure it occurs at the right time and for the appropriate duration. These strategies use sensors and algorithms to monitor system conditions, such as coil temperature, pressure, and airflow, to determine when defrosting is necessary. By optimizing the defrost cycle, these control strategies minimize energy consumption, reduce system downtime, and maintain optimal system performance.