A recently installed PEX waterline in a new wall suddenly shows signs of leakage, with water stains appearing on the drywall. The contractor is concerned about potential damage from fasteners. To verify if a fastener has punctured the PEX tubing, which of the following leak detection methods would be most effective and least destructive for initial assessment?

Question: A recently installed PEX waterline in a new wall suddenly shows signs of leakage, with water stains appearing on the drywall. The contractor is concerned about potential damage from fasteners. To verify if a fastener has punctured the PEX tubing, which of the following leak detection methods would be most effective and least destructive for initial assessment?

Answer options:

• Cutting open the wall immediately where the stain is visible ✅ Using an acoustic leak detector to pinpoint the sound of a leak
• Pressurizing the PEX line with air and listening for hissing
• Injecting a fluorescent dye into the water system

Correct answer: Using an acoustic leak detector to pinpoint the sound of a leak

Explanation: An acoustic leak detector is the most effective and least destructive method for pinpointing a PEX line leak behind a wall. It senses the sound of escaping water, allowing for more precise cutting of the drywall. Cutting the wall immediately is destructive, air pressurization might not be precise enough, and dye injection is for general detection, not specific pinpointing.