About three months ago I discovered in a drive way run that the heater part of the air conditioner set up I have was not working properly. Took it in and had it repaired at that time. Last weekend, went camping and when opening the PopUp discovered water stains and mildew on the side of the PopUp that is underneath the air conditioner unit, that also has the heating element for light weight warming of the PoPuP. I have never had any internal water stains until after that "repair."
I now have rain stains and mildew stains inside. I will take it back to the service and ask them to take another look, I suspect that they did not reseal properly.
What do you do for mildew and rain stains?
It sounds like they did not tighten the roof gasket enough when they did the repair job. Bleach in one form or another is about the only way to get mildew out of the tenting. I would push for the dealership to replace the tenting for you. Good luck.:)