You should check the caulking up on the roof every year or have someone do it for you. The RV dealer or an independent mobile RV tech could do it or, if you are capable of getting up there, do it yourself.
All the caulking around every roof penetration should be checked along with the caulking at the front and rear seams and even, on some trailers, along the sides of the roof.
Any place that looks suspicious or has cracks should be re-sealed with
Dicor self leveling caulk that is available at any RV dealer. Do not use any silicone caulk.
The air conditioner does not usually have any caulk to seal it. There is a rubber/foam gasket that fits between the roof and the air conditioner pan that gets squeezed between the two. The pressure holding the air conditioner on the roof is provided by four long bolts that you can get to by taking off the inside cover of the air conditioner. Those bolts sometimes loosen up a bit and should be checked occasionally - especially on a new unit. As that gasket on the roof compresses over time the bolts can loosen and let water penetrate. You cannot easily see the gasket as it is under the pan so you can't tell by looking at it. Do not grunt down on those 4 hold down bolts - just snug them up a bit.
None of this is rocket science and can be done by anybody who can get up a ladder and operate a caulking gun. No need to take the RV anyplace special unless you are not able to get up on the roof.
Good luck.
๐Barney
2004 Sunnybrook Titan 30FKS TT
Hensley "Arrow" 1400# hitch (Sold)
Not towing now.
Former tow vehicles were 2016 Ram 2500 CTD, 2002 Ford F250, 7.3 PSD, 1997 Ram 2500 5.9 gas engine