Leak Detectors: Quick Reference

Electronic leak detector

  • Handheld device with a sensor at the end of a flexible tube and a small internal pump that draws air past the sensor.
  • When refrigerant is detected, it chirps/beeps.
  • Move very slowly across suspected leak areas: 1−3 inches per second1-3 \text{ inches per second}.
  • Some detectors rely on overall concentration; others rely on a change in concentration. The ones described here detect a change.
  • Establish a clean-air benchmark at the start; to locate a leak, approach until it chirps, pull away to clean air to stop chirping, then re-approach and repeat to pinpoint.
  • Protect the sensor: avoid exposing it to straight refrigerant from a bottle and limit moisture, which can cause false trips or shorten life.
  • Pros: highly reliable for very small leaks; no system prep required.

Ultraviolet leak detector

  • Inject dye into the refrigeration system using a dye tool, run the system to circulate dye.
  • Use an ultraviolet lamp/flashlight to visualize the leak.
  • Disadvantage: leaks in hard-to-see areas may be missed unless you can visually inspect the area.
  • Comparison to electronic: UV requires dye and visual inspection; electronic detects leaks without locating the exact path.
  • Practical note: with UV, you may need to remove components to see the leak; electronic sensors can detect leaks behind coils without disassembly.

Ultrasonic leak detector

  • Detects the audible hiss/noise from gas leaking through an orifice.
  • Handheld wand (or similar) to sweep areas; listens for the leak sound.
  • Works on any pressurized piping system where a leak produces sound.
  • Proximity is important; you must get close to hear the leak.

Halide torch leak detector

  • Uses a propane torch with a side port; Venturi effect draws air into the device.
  • If refrigerant leak contains chlorine, the flame color changes to green.
  • Limitation: ineffective for newer refrigerants that do not contain chlorine.
  • Generally an older method and less common for modern systems.

Bubble solution (soap bubble method)

  • Simple, universal method for any pressurized gas.
  • Apply soapy solution around joints; leaking gas creates bubbles that grow and pop, pinpointing the leak.
  • Particularly useful to determine which side of a joint is leaking and for repairing.

Quick practical tips

  • It can be beneficial to have more than one type of detector on your truck.
  • Learn from peers and experiment to determine your preferred method.
  • These tools can enhance your senses: electronic for detection, ultraviolet for visual, ultrasonic for sound.
  • If you know someone who has tested detectors, ask about successes and limitations.
  • A referenced comparison video (e.g., Eddie’s YouTube test) can provide additional context.