In a troubleshooting scenario where the thermostat contacts are closed, and the compressor and condenser fan motor are short cycling while the blower motor is not running, what could be the cause?

In a troubleshooting scenario where the thermostat contacts are closed, and the compressor and condenser fan motor are short cycling while the blower motor is not running, what could be the cause?

• A. A faulty compressor
• B. A faulty blower motor or blower relay
• C. A shorted transformer
• D. Open contactor

Answer: (B)

The situation described involves the thermostat contacts being closed, indicating that the system is calling for cooling. When both the compressor and the condenser fan motor are short cycling, while the blower motor is not running, it suggests that there's an issue related to airflow or the proper functioning of the components that are responsible for moving air through the system. A faulty blower motor or blower relay is the most likely cause in this scenario. If the blower motor is not operational, it prevents proper airflow across the indoor coil. This lack of airflow can cause the compressor to short cycle because the system may reach the desired temperature too quickly, leading to the compressor and condenser fan motor cycling on and off frequently without the necessary cooling effect. The inability of the blower to circulate air also affects the efficiency of the entire cooling cycle and can lead to compressor damage over time if not addressed. Understanding the roles of the components highlights the reasoning behind this conclusion. The blower motor is essential for moving air across the evaporator coil, allowing for efficient heat exchange during the cooling process. If the blower is inoperative, it not only affects temperature regulation but can also lead to overpressure conditions, causing erratic behavior of the compressor and condenser fan. Thus, the diagnosis points to a problem with the blower

The situation described involves the thermostat contacts being closed, indicating that the system is calling for cooling. When both the compressor and the condenser fan motor are short cycling, while the blower motor is not running, it suggests that there's an issue related to airflow or the proper functioning of the components that are responsible for moving air through the system.

A faulty blower motor or blower relay is the most likely cause in this scenario. If the blower motor is not operational, it prevents proper airflow across the indoor coil. This lack of airflow can cause the compressor to short cycle because the system may reach the desired temperature too quickly, leading to the compressor and condenser fan motor cycling on and off frequently without the necessary cooling effect. The inability of the blower to circulate air also affects the efficiency of the entire cooling cycle and can lead to compressor damage over time if not addressed.

Understanding the roles of the components highlights the reasoning behind this conclusion. The blower motor is essential for moving air across the evaporator coil, allowing for efficient heat exchange during the cooling process. If the blower is inoperative, it not only affects temperature regulation but can also lead to overpressure conditions, causing erratic behavior of the compressor and condenser fan.

Thus, the diagnosis points to a problem with the blower