EPA Section 608 Universal Certification ExamCoreEasy
A technician is performing a leak check on an R-22 refrigeration system. Which of the following methods is generally considered the most effective for pinpointing the exact location of a small leak?
- APressurizing the system with nitrogen and using soap bubbles.
- BUsing an ultrasonic leak detector.
- CUsing a halide torch detector.
- DAdding a fluorescent dye to the refrigerant and using a UV light.
Show answer & explanationAnswer & explanation
Correct answer: D. Adding a fluorescent dye to the refrigerant and using a UV light.
Fluorescent dye, when added to the refrigerant, circulates throughout the system and will glow brightly under a UV light at the precise point of a leak, making it highly effective for pinpointing small leaks.
Why the other options are wrong
- A. Soap bubbles are good for general leak detection but less effective for very small or hard-to-reach leaks.
- B. Ultrasonic detectors locate the sound of a leak, which can be difficult to pinpoint precisely, especially in noisy environments.
- C. Halide torches are older technology, less sensitive, and involve an open flame, which can be dangerous and is generally not recommended.
Fluorescent Dye Leak Detection
A leak detection method where a special dye is added to the refrigerant, circulates with it, and becomes visible under a UV light at the point of a leak.
- Excellent for pinpointing small leaks.
- Requires a UV light for detection.
- Dye must be compatible with system components and refrigerant.
Memory trick: Find the tiny leak, just follow the glowing trail.