Hey folks! I'm curious if solar collectors are a thing around here, not just PVs. I've got a bunch of old glycol-based solar collectors, but I think the glycol has evaporated since I live in a hot tropical area. I'm thinking of reusing the collector plates to set up a DIY drainback system using water. Do you think this is feasible? Has anyone tried this before?
1 Answer
From what I've learned about solar heating, converting those panels into a drainback system is definitely doable! You won't need the glycol anymore, but you must have a storage tank for the water when it gets chilly outside. Just a thought, though—maybe consider fixing the collectors instead of turning them into a drainback system? It could be an option.
I get where you're coming from, but these panels have been idle for almost ten years, so I'm pretty sure the glycol is all gone. Plus, I already have some small tanks on the roof that could work for the drainback. I'm not on-site to fix the panels, and I lack some details about their condition, so I thought this low-tech route might be easier. But yeah, if I fix them, I’d need an expansion vessel, which I’m not sure is even there. Drainback has the advantage of preventing overheating, though! Thanks for your input, I'm leaning toward fixing them!