Turning my indirect water heater into a solar heater.

[minimac]

PVC pipe isn't rated for the temps that even a small collector would see. CPVC is a little better, being rated for hot water use, but my small homemade collector easily produces temps of over 200*F in the summer. It's a great idea and will work well and do what you want to accomplish, but research it, because improperly done, the potential to cause a lot of damage/harm exists.