DIY, Geothermal Wood Stove Make Up Air 

Exactly !

Actually when I installed it was just a drain. But then I discovered that it is working as a geothermal make up air. If I had known that it was going to work like this I would have put two pipes in! Thanks,

Yes and if your stove has the direct make up hook go with it! Thanks,

I'm not sure exactly what you mean but I do capture some of the heat going out my chimney. You can check it out here, ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-epNXCLqbMJI.html Thanks,