If you're trying to document "its not overheating" for the dealership to make a warranty claim, one of these would be a great help: https://www.amazon.com/Non-Contact-Digital-Infrared-Thermometer-Temperature/dp/B07TMFQ73W/ Show that it warms up and works fine for hours, THEN fails without getting any hotter.

You don't really need a $300 IR camera... just use a $12 IR thermometer. Won't be as easy and problems are less obvious, but for the amount of time you need it, just measuring various areas near the doors and windows will do the job.

And IR cameras are just measuring the temperature of the surface, so you can get wildly different results when comparing two different materials. OP comparing glass windows to a brick wall is absolutely useless.

You want to use IR cameras to find areas of a wall that are hotter or colder - which again, you can do with an IR thermometer, you just don't get a fancy picture.