I recently had mine stop up to the point it was leaking water inside the trailer. I used a shop vacuum cleaner after the A/C unit had been running for a while and sucked out the water and whatever was in the line stopping it up. Couldn't actually attach the vacuum to the little pipe, but used my hand around it to get it to work.
This was good because I didn't have to take anything apart.
Good luck with yours.
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