ps1 error on hot tub

I got a used hot tub back in 2014. It is a Gatsby by Jacuzzi and it has been working pretty good over the years. It has two jet pump motors and a 24/7 circulating pump. 2 weeks ago I emptied the hot tub to put fresh water in as I do every 3-4 months. Drained the hot tub, cleaned the sides and...