just took possession of the new cabin about a week ago, and it has three separate heat tapes. On one of them it's clear that it's working as I can feel the heat off the line, but the other two are buried under urethane foam. Just wondering if there is a way to determine if they are working or if I need to replace them (big job). Is there a way to simply use an ohm meter to determine resistance? Perhaps measure amp draw? I have very little experience with the tape, but with temperatures that plummet to -40 below here, I need to become familiar with this quickly! Temperatures are already down in the 20s here in Alaska, so like to get this wrapped up quickly as it's no fun working at these temperatures.