Symbol van Condensation or leak

Hi  I am having water dripping from under door and also seal under door. I cannot see any cables in this area. I be very grateful if anyone had any issues like this or thoughts what is[You must be registered and logged in to see this link.]
 causing this! .It doesn't happen all the time and stopped after a couple hours.. I just used the van this weekend. I enclose photo of the drips. 
Thank you 
Sam 



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