This is such an illustrous and knowledgeable group, that I figured I might as well post this question here. The subject is hot water in PEX tubing in a hydronic in-floor heating system. My system was installed well over 10 years ago. It works great and I would not want to be without it. However, the installers failed to leave a layout plan, they are out of business and I have no idea, where exactly the tubing is in the floor. The thought came to mind that I could use an infrared camera or something like it? With the system turned on, the tubing should become visible? Any ideas?