Refrigerant leaks occurring in a system charged with Freon are detected using____________________?
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Answer: A. halide torch which on detection produces greenish flame lighting
Explanation
Refrigerant leaks in systems charged with Freon are detected reliably using a halide torch connected to a gas source. In the presence of halogenated Freon gases, the torch flame changes color to a distinct bright green or blue-green hue. This color reaction provides a sensitive visual method for service technicians to locate microscopic joint leaks. Halide torches burn alcohol or propane, drawing air samples across a hot copper element to detect halogenated hydrocarbon leaks. When halogen molecules touch the hot copper surface, copper halide forms, instantly altering the combustion flame color. Modern technicians also utilize electronic leak detectors that sense halogen gas ionization for rapid maintenance checks.
Option B sulfur sticks produce white smoke when brought near ammonia leaks rather than detecting halogenated Freon gases. Option C using reagents is a cumbersome chemical method unsuited for quick field inspections of refrigeration piping joints. Option D smelling is unreliable and hazardous because many modern Freon refrigerants are completely odorless and toxic.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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