EPA Section 608 Universal Certification ExamType I (Small Appliances)Hard
A technician is performing a leak check on a small appliance that uses R-290 (propane). Which of the following leak detection methods is LEAST recommended for this hydrocarbon refrigerant?
- AUltraviolet dye leak detection.
- BElectronic leak detector specifically designed for hydrocarbons.
- CHalide torch leak detector.
- DSoap bubbles or liquid leak detector.
Show answer & explanationAnswer & explanation
Correct answer: C. Halide torch leak detector.
A halide torch leak detector uses an open flame to detect halogenated refrigerants. Using an open flame near a highly flammable hydrocarbon refrigerant like R-290 (propane) is extremely dangerous and should never be done.
Why the other options are wrong
- A. Ultraviolet dye detection is a safe and effective method, especially for small, hard-to-find leaks, and compatible with R-290.
- B. Electronic leak detectors designed for hydrocarbons are very effective and safe for R-290.
- D. Soap bubbles are a safe and effective general leak detection method for any refrigerant, including R-290.
Flammable Refrigerant Leak Detection
When dealing with flammable refrigerants, leak detection methods must strictly avoid any ignition sources to prevent fire or explosion hazards.
- R-290 (propane) is highly flammable.
- Halide torches use an open flame – highly dangerous.
- Electronic detectors (HC-specific), soap bubbles, and UV dyes are safe.
- Prioritize safety and avoid any potential spark or flame.
Memory trick: For 'flammable' gas, no 'flame' for a check, or you'll have a disaster, not just a speck!