pretty sure sand is NOT supposed to show up here....
I'm doing a modest happy dance at the moment.
Decided to tinker with the pool this morning. Thought I'd get an idea of how blocked the return lines actually were.
I couldn't unscrew the outlet from the heater, so I took off the closest jandy valve lid, (that leads to the spa). It was clear, no sand at all, flushed it with the garden hose and all looked fine.
With a high pressure nozzle on the hose I flushed out as much sand as I could from the open heater inlet. Then shoved the hose in as far as it would go.
Looked over and there's a trickle of water flowing through the jandy valve, then a lot of debris, more water and sand.
I hooked the lines back up, leaving the jandy valve open, turned on the pump, and it worked. First lots of sand, then a nice full flow of water.
I put the jandy valve back together, and right now the pump is working and the filter is on recirculate!
Tomorrow I'll check the laterals and filter sand.
It seemed too easy, so maybe I'll delay on being
very happy until the pool is blue and clear again.
But still :-D