They aren't heated when they are transported, that being said I leave my TV's in the camper year round. I think that you would just want to avoid rapid temperature fluctuations due to condensation.
1998 Jayco Eagle 302FK (Honda EU3000is)
2016 GMC Sierra Denali 3500HD 4x4 Duramax/Allison
2003 Honda Aquatrax F-12X Turbo