I don't understand "air conditioner" + "behind the couch." The A/C is mounted on your roof, correct? If so, it drains its condensation onto the roof, then it runs off the closest low spot it can find. So as Kevin says above, go to the roof and verify draining. If your A/C is more than a couple years old, Clean It. Plastic cover comes off, then the ducting at the front of the unit, allowing access to the Evaporator Coil. That Coil drains Condensate into a Tray under it, that probably has a Drain at the Left and Right ends. I find I can hose the evaporator if I use a shield (cutting board, expired license plate) to keep spray out of the discharge area below and forward of the evaporator. You'll soon see if it's draining!
Otherwise, start feeling around, for water drips from piping, probably at the connections. Be careful around the bottom of the sink near the faucets! At least on my cousin's, with a stainless "drop sink," there's a razor sharp edge on a stiffener by the faucet connections.
Refrigerator also has a Condensate Drain. Norcold has a catch cup on the outside of the fridge (through the lower access panel) that's supposed to evaporate before it ever overflows. Dometic uses a tube leading to a dedicated hole that drips on the ground. Many route that tube out the louvers in the lower vent cover.
