This is complete setup for ESP32 running ESPHome for Mppt controller like this one: http://www.el-car.auto.pl/?75,regulator-grzalek-mega-pwm-mppt-3000w for heating up You water or/and floor heating.
YouTube: https://www.youtube.com/playlist?list=PL5iWFxkiX-kjziS4BVB5gSOfbjKgxe14X