Leak from solar panel roof entry

I noticed some tiny pimples on the inside ceiling above the wardrobe door on my Nuevo. I pressed one with a finger and it disappeared. I studied the digit but couldn't see any wet but I was curious - it could be damp so I looked above the door inside the wardrobe, and peeled off a decorative strip where the solar cable (s - in my case- ) ran across above the door towards the Sargent box. The wood in there was definitely damp. I made an arrangement to visit a caravan / motorhome repairer who diagnosed the problem and quickly fixed it. It was a good job I was doing something else in the camper in January otherwise it would have got serious.

The point of the post is this: Autosleepers fitted a solar panel, and the cable goes inside through the roof via a rectangular white plastic cowl above the wardrobe. The cable then runs round the top of the wardrobe and down to the Sargent box inside a box section. (Thinks - Why on earth don't they enter the cable into the roof roof directy above the Sargent box, saving running the cable round the top of the wardrobe??)
Anyway this white plastic cowl is made of a type of plastic to which silicone sealant does not stick. The cowl is 'stuck' to the roof of the vehicle. On top of that Autosleepers do not scratch the joint area in order to increase the adhesion of any sealant used. The caravan / motorhome repairer told me that the only thing to use in this situation is Polyurethane sealant which will stick properly to plastic and metals. In my case, as Autosleepers (I can't be bothered to type Auto Sleepers in full every time, sorry) had used silicone, the joint had split after a few years, and rain was finding its way in. Luckily I had spotted it just as it had started to leak.

It's not just AS.
Yesterday a mobile engineer found the same problem on a French van, a Rapido, there was a telephone enquiry going on, I didn't get the whole thing but Sikaflex was mentioned. You would think that who ever fit the panels, manufacturers or third party fitters would be knowledgable on what to use.

However seeing that some AS operatives don't know or don't care about over tightening screws and ripping the threads out, would that type just use what sealant is laying around rather than select what is correct for the job.

rgermain wrote:When I fitted our solar panel, I use the correct entry box on the roof and filled it with almost 3/4 of a tube of Sikaflex, which I had left over. I also pumped loads over the panel fixing screws.

No leaks and hope I never have to remove the box.
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Richard

Yeah I'm the same, sikaflex is definitely the way to go. Silicone sealant just isn't hard wearing enough imo and the joint breaks down as in the OP.

Don't get me started on Rapido's non existent Quality Control. I had a brand new one with an electric bed, which I returned to Brownhills three times to fix. They failed, I got the workshop manual from the bed manufacturer and eventually tracked the fault down to Mr Rapido smoking Galouises and drinking red vino instead of pushing an 8 way plug and socket together properly. Whoever did it would have known at the time that one of the 8 pins in the plug was not connecting but couldn't be bothered to push it in properly.
Never again. They look all flashy but be prepared with a good workshop if you want it to actually work.