Two questions: fridge OOPS! and battery boost relay

Go to this link at Winnebago.

https://www.winnebago.com/owners/owner-resources/guides-and-diagrams

Scroll down to Wiring Diagrams then select your year and Itasca model. Find the diagram that shows the "Battery Mode Solenoid", which is what Winnebago calls the solenoid that connects the House and Chassis batteries when the ignition switch is on.