Chinook RV

We have been unable to get it to work plugged in or on generator. We are picking it up tomorrow so I will have more time but previous owners from Florida never used it and remember it coming on once on a cold night in Florida and again last winter. I have checked all breakers and I am sure of the honesty of owners. They never turned it on but I guess it is always powered so comes on at low temps but won't come on for me even set at highest setting! (We did leave it on for several hours.)
Thanks, Bryon

Does it draw power when you turn it on? Possible that the coil got burn out/cut, and does not work anymore. Do not have one in my rig, so I just guess. Can you check the coil with continuity meter (obviously with power off)?