leaking airconditioner in Jayco poptop

More than likely the drain hose is kinked or blocked. Had exactly the same problem with our first van a jayco freedom ptop.
The trouble is the hose is routed through the wall cavity! What I did was to get a length of micro retic pipe, and from under the van, find the hose outlet, then I pushed the retic pipe up the drain hose, it hit a blockage around half way in, but by gently twisting and pushing it suddenly went through and water started to drain out.
I simply left the tube inside the hose to keep the pipe open.Never had a leak again.

Could be something as simple as a spider web.
ozjohn.

Not sure of the layout but get to one end of the drain and blow out the drain with an air compressor to ensure the drain is completely clear.
Mid the mess though.

We have put a fine piece of plastic cable through the drain tube, I pulled the end, where is is connected to the drainage tray off and put the same cable though that. I blew into the drain hose, with no restriction. Where the tube comes out of the drip tray and to where it enters the wall to drain down to out side is nearly level. I have now put a cork between the hose and the unit to try and get it to slope down without the drain hose kinking up higher than the drip tray. I have just turned the Air Con on again and am sitting here with fingers crossed to see if this helps

Tape the hose of a wet/dry vacum cleaner to the end of the drain tube with a bit of gaffer tape and give it a really good suck ....

Will clean all the crap out of it. Also, I sometime then put a bit of water into the drip tray to rinse the drain pipe out. ....