mzbk2l

Great tips, but I couldn't get past the idea of slowly disabling more and more of the tubes on my panels. I went a different route and patched them from the outside, leaving the tubes still functional. For the most minor of leaks, a coating of RTV was sufficient to stop them - but most leaks required more than that. Sitting in my garage from the installation of my mist cooler system was some nice stiff vinyl tubing with an ID almost the same as the OD of the tubes in my panels. I cut 4" lengths of that tubing, slit it all the way down one side, and then slid it over the leaking fafco tubes with a generous helping of RTV to seal the deal. So far, none of the tubes I've repaired that way have leaked again, although I suspect I'll run out of leftover vinyl tubing long before I run out of leaking fafco tubes. Note that I have flat roof sections hidden by parapets, so I had no need to paint the patches to match the panels. If appearance is a concern to you, that might be an added step you need to take.