Hi all! New member, first post!
I’ve only owned a pool for a year so I’m still learning. I want to keep this solar heating panel setup as low-cost as possible since I want to test its effectiveness for a season or two before putting more time, effort, and money into any permanent change.
Do you see any issues in the first draft of my schematic? Anything I haven’t thought of?
Pictures illustrate better:

Please excuse the weeds!

Some questions
1) Since the whole system is separate from the pool filter/pump, it’s only under unidirectional pressure when turned on, do I actually need a vacuum release or any other valves? (The panels came with a diverter valve that I don’t think I need, maybe I can use that as drainage at D (see picture), if needed?)
2) Is there another way to connect joints besides gluing rigid PVC fittings for joints ABC? I like the impermanence of a flexible PVC coupling with clamps, but I don’t think they can withstand sun/heat and pressure? For example the description here says may use for “non-pressure drain”. Any other options?
3) Lower priority: Possible near-future upgrade - The current plan involves just manually plugging the pump in when the sun is out and trying to remember to unplug it before it starts cooling off. Is a simple automation system possible for under $100? I’m thinking 2 wireless app-enabled temperature sensors, a smart outlet (z-wave or similar), and software to connect the two and decide when to turn on/off (IFTTT or Home Assistant?). ( I understand this may be more appropriate to post in the Automation forum but they seem much more hardcore than I need!)
TIA for any comments/advice/suggestions!
I’ve only owned a pool for a year so I’m still learning. I want to keep this solar heating panel setup as low-cost as possible since I want to test its effectiveness for a season or two before putting more time, effort, and money into any permanent change.
Do you see any issues in the first draft of my schematic? Anything I haven’t thought of?
Pictures illustrate better:

Please excuse the weeds!

Some questions
1) Since the whole system is separate from the pool filter/pump, it’s only under unidirectional pressure when turned on, do I actually need a vacuum release or any other valves? (The panels came with a diverter valve that I don’t think I need, maybe I can use that as drainage at D (see picture), if needed?)
2) Is there another way to connect joints besides gluing rigid PVC fittings for joints ABC? I like the impermanence of a flexible PVC coupling with clamps, but I don’t think they can withstand sun/heat and pressure? For example the description here says may use for “non-pressure drain”. Any other options?
3) Lower priority: Possible near-future upgrade - The current plan involves just manually plugging the pump in when the sun is out and trying to remember to unplug it before it starts cooling off. Is a simple automation system possible for under $100? I’m thinking 2 wireless app-enabled temperature sensors, a smart outlet (z-wave or similar), and software to connect the two and decide when to turn on/off (IFTTT or Home Assistant?). ( I understand this may be more appropriate to post in the Automation forum but they seem much more hardcore than I need!)
TIA for any comments/advice/suggestions!