Can you please post particulars about your pool/Spa? Configuration? Spa Spillover? Water features? Number of skimmers and drains etc. That would help. So would pictures of the pool/Spa.
www.troublefreepool.com
This looks to be a SPA or water feature circuit:
View attachment 616912
This is an electrical junction box.
View attachment 616913
This is an abandoned pump...likely a pressure cleaner pump:
View attachment 616914
This is the main pool circuit. The pressure/return side valve is currently set to flow water through the chlorinator:
View attachment 616916
This is a product made by Orbit. No idea what it is or what it does...may have been part of the pressure side cleaner.
View attachment 616917
This gives you the basics. Without knowing more about the pool/Spa/Features, hard to confirm or validate. Post what you can.