What is the main purpose of capacitors in HVAC systems?

The main purpose of capacitors in HVAC systems is to store electrical energy and provide a boost to start motors. In many HVAC applications, particularly with motors such as those found in compressors and blowers, the starting current requirements can be significantly high. Capacitors provide a temporary increase in voltage and current to help overcome the initial inertia of the motor, allowing it to start more easily and efficiently.

When the motor begins to turn, the capacitor is rapidly discharged, supplying the necessary extra energy required for startup. Once the motor is running and has reached its operating speed, the capacitor's role diminishes, and it may be taken out of the circuit in some designs. This crucial function not only helps ensure that the motor starts reliably but also improves the overall performance and longevity of the system.

The other options, while relevant to HVAC system performance in various ways, do not accurately describe the primary role of capacitors. For instance, reducing energy consumption pertains more to system design and efficiency rather than the function of capacitors. Filtering dust and pollen relates to air filters, and monitoring system efficiency involves sensors and control systems, not capacitors. Thus, the specific role of capacitors in providing a starting boost to motors is critical in HVAC applications.