If you’ve ever needed to locate a radiant tube hidden under the floor but have been unable to find that careful diagram you made, your local fire department may be able to help. Ask them if they have a thermal-imaging camera. In exchange for a donation (fire departments always need money for something), you may be able to schedule a visit from a firefighter with camera in hand. If the pipe is hot, the camera will show the exact location of the pipe you are trying to avoid, or perhaps fix.
If your local fire department doesn’t have a thermalimaging camera, providing one is a great communityservice project for a homeowners’ association to undertake. This type of camera costs less than $3000.
Ernie Mainland, Petoskey, MI
