I just got a couple used solar panels off craig's list that are in decent shape. I am in the process of determining how I am going to plumb these and I am curious why a vacuum breaker would be required? If it is not present wouldn't the water just stay in the pipes and in the solar panels? Is the vacuum breaker an absolute must?
Also, why wouldn't you want some water to stay in the panels some time? for example instead of running the pump all day long I've been thinking I may try running the pump for 5 minutes every hour or so to flush the warmer water out of the panels and replace it with cooler water. Is this not a good idea? If not then why isn't it?
Also, does anybody happen to know the crush resistance of schedule 40 PVC? Once I mount the panels on top of my shed I will need to run the pipes under my driveway (just stone, not paved) and want to see if I can just direct bury the PCV (planning about about 1ft deep) or if I would need put put them inside of something.
I'd be open to suggestions if anybody has any on preventing the pipes from getting crushed. I thought about getting 1/2 block cinder blocks and putting them in there or even pouring concrete, but both of those options seem like a real pain. I also thought about the schedule 40 gray conduit but I don't think that would gain me anything.
All thoughts are appreciated.