MACS 609 Certification Practice Exam

What transports ultraviolet dye through the A/C system?

1. Refrigerant oil

2. Coolant fluid

3. Compressor gas

4. Ventilation air

The correct answer is: Refrigerant oil

The correct answer is that refrigerant oil transports ultraviolet dye through the A/C system. In automotive air conditioning systems, the refrigerant oil plays a critical role in ensuring that the components operate smoothly and efficiently. When ultraviolet dye is introduced to the system, it is mixed with the refrigerant oil. As the refrigerant circulates through the A/C system, it carries the dye along, allowing for effective detection of leaks. Ultraviolet dye is commonly used as a diagnostic tool; by adding it to the refrigerant oil, technicians can identify leakage points when using a UV light, as the dye will fluoresce. This makes it easier to pinpoint issues without extensive disassembly of the A/C system. Other options like coolant fluid, compressor gas, and ventilation air do not serve the purpose of transporting the dye through the system. Coolant fluid is primarily involved in engine cooling rather than A/C operation. Compressor gas refers to the refrigerant in a gaseous state, which does not directly carry the dye; instead, it is the oil that facilitates this process. Ventilation air is related to the airflow within the cabin and does not interact with the refrigerant or the dye in a way that would transport it throughout the A/C system.